Wes Welker -- PASSIN' OUT $100 BILLS ... After Huge Kentucky Derby Victory

Wes Welker channeled his inner Lloyd Christmas at Churchill Downs this weekend -- passing out $100 bills to strangers after winning THOUSANDS of dollars on the Kentucky Derby.

Unclear what bet hit for the Denver Broncos receiver (trifecta? boxed trifecta? super trifecta?), but Welker left the cashier with STACKS of hundred dollar bills.

And people at the race track tell us ... he was in such a great mood, he handed out several $100 bills to complete strangers to celebrate his big victory. We're told he handed out at least $600.

Eventually, race track security advised Welker to move toward the exit before things got chaotic ... but dude, STRONG MOVE, WELKER.