A retired city firefighter who posted racist and anti-Semitic rants on Facebook is now officially on the ballot to head the FDNY union, sources said.

Kenny Specht, whom The Post exposed for calling an Orthodox Jewish couple that lost seven kids in a Brooklyn fire “dirty bastards,” was nominated for the empty seat with the Uniformed Firefighters Association during a general nomination meeting at the JFK Hilton.

The ballots will be mailed out March 1 to all active city firefighters and must be returned by March 21.

Specht also jeered African-Americans with rants like, “I’ll see your black power sign and raise you one proud white power unapologetic male! Power on!”

He did not return calls for comment.