If Bernie Sanders wins the Democratic nomination for President ... he might have this endorsement from one of the biggest pop stars in the world to thank.

Ariana Grande just shared a couple photos with the 78-year-old Vermont Senator, thanking him for hitting up her concert in Atlanta Tuesday night and "making my whole night and for all that you stand for !"

She went on to say she's doing her best to register young voters and has already gotten more than 20k sign-ups at her shows. She added ... "i will never smile this hard again promise."

From the looks of it ... Bernie might not either!!!

Sanders is in town for tonight's fifth primary debate, which will feature 10 contenders for the Democratic nomination. Not that he needs the energy boost ... but ya gotta think a plug from Grande will provide one anyway.

BTW -- this isn't the first time Ariana and Bernie have had a noteworthy connection ... last month she posted "baby how u feelin" on Twitter, and he replied by tweeting he's ready to fight for Medicare for All.

A Lyft driver pulled a female passenger out of his car, and allegedly started to attack her -- kicking off a chain reaction of fights with concerned passersby.

TMZ got a hold of this WILD surveillance video recorded Tuesday afternoon in L.A., and it starts with the car -- which has the Lyft emblem in the back window -- parked curbside along busy Melrose Avenue. Then the male driver hops out, and pulls a young woman from the seat behind him and starts dragging her out of the vehicle while tossing her stuff out at the same time.

The woman, actress Alessandra Starr Ward, tells TMZ the whole thing started when she started playing a song called "Te Bote" from her phone. The driver demanded she turn it off, she refused, and they started arguing. He allegedly threatened to boot her from the car, and she told him she'd call police if he did.

In the clip, you can see Alessandra fighting back, but the driver pushed her down and knocked her over. Drivers in other cars saw it unfolding and a few guys stopped to help.

That's when it really hit the fan ... several guys teamed up on the Lyft driver, who continued fighting back, and in the scuffle ... Alessandra got knocked down again. It took one guy putting the Lyft driver in a chokehold to finally calm things down.

We're told nearby police officers were flagged down, and cited the Lyft driver for misdemeanor battery. As for Alessandra, she says she went to the hospital and was diagnosed with a concussion. She also says she has bruises all over her body, a sprained ankle and a black eye.

She tells us Lyft needs to vet its drivers, as this shouldn't happen to anyone. It's unclear if she plans to pursue legal action against the rideshare company.

The pregnant woman who was allegedly punched in the head repeatedly by NFL running back Mark Walton called cops sobbing and told them, "My boyfriend beat me up!"

It's all in new 911 audio obtained by TMZ Sports, in which you can hear a clearly upset woman explaining to dispatch how the ex-Miami Dolphins player roughed her up Tuesday in Davie, Fla.

During the call, placed about 10 to 15 minutes after the incident, the sobbing woman says Walton had hit her and then left the scene in a car.

What's interesting about the call is dispatch recognized Walton's name right away ... asking the woman if she was talking about "the football player."

Eventually, cops arrived to the scene ... and, per a police report obtained by TMZ Sports, officers say the woman told them Walton pushed her against a wall and punched her several times in the face and head, even though he KNEW she was 5 weeks pregnant.

Cops say they noticed the woman had swelling on her left eye.

22-year-old Walton was ultimately arrested and booked for aggravated battery against a pregnant person -- a 2nd-degree felony which carries a maximum sentence of 15 years in prison.

Walton showed up in a Broward County courtroom in cuffs and a beige jumpsuit to face the charge Wednesday ... and was ordered to have no contact with the woman once he's out of jail.

Josh Duggar has Homeland Security crawling around the car dealership where he works in Arkansas, and it's related to a federal investigation ... TMZ has learned.

Agents went to the dealership in Springdale, AR in connection to a federal probe ... according to sources close to the situation. There were reports the feds had raided the Duggar family home, but we're told that's not the case. Agents have only been at Josh's place of employment ... at least for now.

It's unclear exactly what the nature of the investigation is, or if Josh was the target. A Homeland Security spokesman would only confirm agents were at the dealership.

The Duggars rose to fame thanks to a pair of reality shows, '19 Kids' and "Counting On." But, as we reported, TLC eventually pulled the plug on '19 Kids' in 2015 following Josh Duggar's child molestation scandal.

Josh's only current legal dispute, that we know of, is a lawsuit filed against him for real estate fraud.

A Duggar family spokesperson says it's not true "any member of our family is the target of any investigation of any kind." The spokesperson added, "Living a life in the public's eye has taught us that it is best not to reply to every rumor and piece of 'fake news' that is circulated online. It would be a full-time job if we attempted to do so."

Story developing ...

Aaron Carter's going to have to wait at least a year to contact his brother because a judge just granted Nick a restraining order against him.

Aaron was a no-show in court in Vegas Wednesday for the hearing -- Nick did attend -- so the judge had an easy decision. The order will stay in place until November of next year.

The order comes a day after Aaron came out on the losing end of another restraining order hearing with his twin sister, Angel. Along with being prohibited from having any contact with her or her family for a year, the judge also enraged Aaron by telling him he's too dangerous to possess guns.

He went nuts in court, screaming that he would just go to another state to stock up and threatened to leave the courtroom ... but the judge ordered him to sit down.

Aaron's anger was still on display outside the courthouse when our photog tried to talk to him.

As we reported ... Nick first sought out legal protection in September after Aaron allegedly threatened to kill his pregnant wife. At the time, Nick claimed he was forced to seek the order against his younger brother "in light of Aaron's increasingly alarming behavior and his recent confession that he harbors thoughts and intentions of killing my pregnant wife and unborn child."

Aaron blasted Nick online, saying he was done with him for life, but insisted he doesn't wish harm on anyone ... especially family.

Angel followed Nick's lead just days later and also got a restraining order. She claimed Aaron threatened to send hit men after her following a disturbing phone call.

Nick also alleged Aaron told Angel he was diagnosed with schizophrenia and bipolar disorder ... something Aaron later claimed on Dr. Phil himself.

As we told you ... Aaron was briefly hospitalized last week, which his mother, Jane, attributed to the stress of the family drama. Of course, Jane's dog-smacking incident and subsequent squabble with PETA probably didn't help alleviate Aaron's stress.

Kanye West's plan to build an amphitheater on his ranch is drawing the ire of officials in Wyoming ... and they're ordering him to put the brakes on his construction project pronto!!!

Park County Wyoming Planner Joy Hill tells TMZ ... the County is ordering Kanye to cease construction on his property because he broke ground without a permit and that's a big no-no.

As we reported ... Kanye submitted docs to build a 70,684-square-foot amphitheater on his sprawling Monster Lake Ranch, and there were construction crews on the property moving large amounts of land to clear a footprint.

We're told Kanye's team was told to stop construction when county officials visited the site after he submitted his building permit application, but subsequent visits to the site by officials showed his team ignored the mandate and kept working.

And, get this ... we're told Kanye's proposed meditation space was on the agenda at a Tuesday meeting for the Park County Planning and Zoning Commission, but the topic never came up because a few hours prior, Kanye's team notified the commission he was changing the intended purpose of the site to residential use.

Now, we're told Kanye's about to get a letter from the County telling him to put an end to construction ... and he's gotta submit a whole new building permit application.

A$AP Rocky just got catapulted to "primary" status in the impeachment investigation of President Trump ... due to the EU Ambassador's testimony about a phone call regarding the rapper's Swedish assault case.

Rocky got roped into Wednesday's hearing because EU Ambassador Gordon Sondland said while he was sitting in a restaurant in Kiev on July 26 ... Trump called him and the "primary purpose" of their chat was A$AP.

Sondland testified Wednesday they mostly discussed A$AP's imprisonment in Sweden ... despite claims the phone call involved Trump inquiring about the Ukrainian government investigating Joe Biden and his son, Hunter.

As you'll recall, the rapper was jailed in Sweden for nearly 5 weeks as he awaited trial for assault following an altercation with a man on the street. He was eventually found guilty by a panel of judges, but with no further jail time ... Rocky bolted back to the States.

Trump was very vocal about the unfair treatment of Rocky and his administration got involved ... and Sondland says that's what they discussed on that July 26 call.

However -- pertaining to the impeachment investigation -- Sondland later testified the phone call also "included the subject of investigations" into the Bidens, and stated there was a quid pro quo established between Trump and Ukraine.

Jussie Smollett has taken the offensive ... he's now suing the City of Chicago, claiming officials created a narrative that he was the mastermind of a hoax attack, and that has cost him dearly.

In the lawsuit, obtained by TMZ, Smollett notes the Osundairo brothers were held for 47 hours and they adamantly denied any involvement in the assault. He says it was only after they were assured they'd get immunity that they started spinning the tale of a fake attack on the streets of Chicago.

Smollett insists the primary attacker was a white male.

He says to this day he doesn't know what involvement, if any, the Osundairo brothers had in the attack. He thinks the brothers were lured into the smear campaign by cops.

Jussie is suing the City, the Osundairo brothers and several officials, including Police Superintendent Eddie Johnson.

As we reported, the City of Chicago is suing Jussie to recoup the costs of the investigation.

There's whitewashing in Hollywood, and then there's this -- a studio exec thought it would be a good idea for Julia Roberts to play Harriet Tubman ... according to the writer of the NEW film, "Harriet."

Screenwriter Gregory Allen Howard says the ridiculous scene went down more than 25 years ago in a pitch meeting about the Tubman project. Howard says the exec told the room ... "This script is fantastic. Let's get Julia Roberts to play Harriet Tubman."

Roberts was widely considered America's Sweetheart at the time after starring in a string of hits like "Steel Magnolias," "Pretty Woman" and "The Pelican Brief."

Howard says when someone pointed out to the studio exec that Tubman was black and Roberts shouldn't play the role, he replied ... "It was so long ago. No one is going to know the difference."

Thankfully, the Hollywood honcho didn't get his way, and flash forward to 2019 ... Howard's movie about the legendary abolitionist who led hundreds of slaves to freedom via the Underground Railroad is finally in theaters.

Of course, the casting of black British actress Cynthia Erivo was also criticized ... because she's not African-American. Can't please everybody.

Taylor Swift may be locked and loaded to go after Scooter Braun Sunday at the AMAs, but we've learned she'll be talking to an empty chair because Scooter will be thousands of miles away.

Sources with direct knowledge tell TMZ ... Scooter's not scared of what Taylor might do ... fact is, he never planned on showing up for the show. He'll be in Tampa, Florida supporting one of his artists who's performing there ... in case you're not familiar, her name is Ariana Grande.

As we first told you ... Scooter's getting death threats from loyal Taylor fans in the wake of their idol claiming Scooter and other Big Machine honchos were holding her first 6 albums hostage.

Our sources say Taylor -- who's getting an award for Artist of the Decade -- plans to weave her anger toward Scooter and Big Machine into her acceptance speech, but there won't be awkward cutaways of Scooter, and that kind of deflates the balloon.

And, there's more intrigue ... Ariana and Taylor are both nominated for Artist of the Year and Favorite Female Artist Pop/Rock at the AMAs. It'll be interesting if Ariana wins since she's squarely in Scooter's corner.

The speeches could be super entertaining.

Charles Barkley says there's "no excuse" for saying he would "hit" a female political reporter -- but insists the whole thing was an attempted joke gone bad.

Axios reporter Alexi McCammond says she was talking with the NBA legend about who he's supporting in the upcoming Presidential election ... and that's when he said, "I don’t hit women, but if I did I would hit you."

Here's the backstory ... McCammond says Barkley was initially explaining why he supported Gov. Deval Patrick -- former 2-term gov. of Mass. -- but then changed up and said he was supporting Pete Buttigieg.

When McCammond questioned him about the switch, Barkley allegedly made the comment about hitting her.

McCammond says she objected to the comment and Barkley told her she "couldn't take a joke."

Barkley has since issued an apology ... saying, "My comment was inappropriate and unacceptable."

"It was an attempted joke that wasn’t funny at all. There’s no excuse for it and I apologize."

McCammond is now reacting to Barkley's apology -- saying, "The comments Charles Barkley made to me are not acceptable."

"Threats of violence are not a joke, & no person deserves to be hit or threatened like that."

Dog the Bounty Hunter wants it known -- he's NOT dead like the Internet might have you believe ... and we got our hands on a good old-fashioned "proof of life" photo to back it up.

The reality TV star took this hilarious photo of himself Tuesday holding a handmade "I'm Alive!" sign in one hand and that day's Denver Post to prove he is, in fact, still with us. We're told this was in response to a fake death story that was going around on Facebook.

Tons of fans were flooding Dog's social media with condolences and "RIP" posts, and our sources say Dog's team even reached out to him to make sure he was all good.

We're told Dog was on his way to a workout when his phone started blowing up and he first heard about the hoax -- which claimed he'd died because his grief over his late wife, Beth Chapman, caused a flare-up of his recent heart problems.

David Guetta and his girlfriend -- but definitely not his fiancee -- are still going strong, and reminding everyone they're one of the hottest and fittest couples out there.

The EDM superstar and Jessica Ledon hit up the beach Tuesday in Miami and went through the full course of PDA -- hugging, kissing, and lovingly holding hands.

The shirtless DJ and the curvaceous actress are a sight to behold, as is the rock on her ring finger.

Don't get too excited, though ... as we told you last year, David and Jessica are NOT engaged because Guetta doesn't believe in marriage anymore. That giant diamond she's flaunting is a promise ring she got from him, vowing "love and commitment" ... but no wedding.

Guetta was married for 24 years before getting divorced in 2014, and he and Ledon have now been dating since 2015.

Seems like the promise ring's doing the trick.