Greg Fischer's mayoral campaign was endorsed by the Louisville Professional Fire Fighters, Local 345 on Monday.
The endorsement is significant because it is the first group of city employees to endorse Fischer, a Democrat, and because it comes from a group that is disgruntled with Mayor Jerry Abramson's administration.
A group of some 800 firefighters recently reached a $45 million settlement with the Abramson administration over a wage dispute that stretches back decades. It also had trouble negotiating a new contract with Abramson, and went four years without a contract before signing one two years ago.
Union president Craig Willman said the group was impressed by the way Fischer "continuously said 'we' instead of 'I.' He's about inclusion and it seems to us that he's interested in best practices and will have an open-door policy."
Fischer said he was "honored" by the endorsement.
The firefighters are the eighth union to endorse Fischer. Fellow Democrat Jim King is second with five union endorsements, including the coveted Jefferson County Teacher's Association which announced its picks last week. There are eight Democrats vying to win that party's nomination in May primary.
The JCTA also endorsed Chris Thieneman on the Republican side. Thieneman faces Hal Heiner and Jon Robertson in that party's primary election.