The state’s Joint Commission on Public Ethics is standing by...

An Antifa street thug was sentenced Wednesday to 18 months in prison for the beatdown of a Trump supporter after a right-wing event at a Manhattan club.

David Campbell, 32, pleaded guilty in September to two counts of felony assault for pummeling a 56-year-old man as he left A Night for Freedom party organized by conservative activist Mike Cernovich.

Manhattan prosecutors say that Campbell followed the victim from the Hell’s Kitchen venue Jan. 20, 2018, and punched and choked him. Campbell was one of about 80 Antifa protesters demonstrating outside the event.

Cernovich told The Post after Campbell took a plea deal, “Now that the criminal case is closed, I will also be taking legal action against Mr. Campbell and his confederates. It is time to find out who is funding Antifa.”

On Tuesday, a pair of Proud Boys convicted at trial of attempted gang assault for a skirmish with Antifa agitators protesting a Gavin McInnes event were sentenced to four years in prison.