Colorado Political Candidate Arrested for Felony Child Neglect in Key West

1:00 PM PST -- Frederick Alfred Jr. has been dropped by the Chainsaw Caucus just weeks after their endorsement. They tell TMZ ... "We take child safety and parental responsibility extremely seriously, and these allegations are inconsistent with the standards we expect from candidates we support. We have no further comment at this time."

A Republican running for a state senate seat in Colorado was arrested in Florida ... after cops say his daughter started drowning in a pool when he left his kids unattended while going to the bar for some booze.

Frederick Alfred Jr. was arrested Monday in Key West on two counts of felony child neglect without great harm.

According to the police report, obtained by TMZ, cops say his 4-year-old daughter began drowning in the pool, became unconscious, started foaming at the mouth, and eventually needed CPR from someone at the pool.

Police say his 6-year-old son swallowed water and also needed medical attention after attempting to save his sister.

The report says 38-year-old Alfred was MIA for around 6 minutes after someone called 911 ... and when he showed up, he was holding an alcoholic beverage.

Police say Alfred told them he left his two kids alone at the hot tub so he could go to the bar and get some booze ... claiming he was only gone for 5 minutes.

Cops say Alfred reeked of alcohol ... and they got his bar receipt, which apparently showed he purchased two cocktails. He was booked into the Monroe County jail.

Alfred lives in Commerce City, Colorado and is running for a state senate seat in a district north of Denver. He is the only Republican candidate running for the seat.

On his campaign website, Alfred proudly touts his role as a father and says he's running to ensure parental rights are respected.