MIAMI (CBSMiami) – Flip-flops are frequent in politics, and in South Florida, this is a biggie.

Last year, Hialeah Mayor Carlos Hernandez supported Julio Robaina, Miami-Dade Mayor Carlos Gimenez’s chief rival.

This year, the leader of Miami-Dade County’s second-largest city is endorsing Gimenez instead. CBS4 news partner The Miami Herald reports Hernandez threw his support behind Miami’s mayor at a noon event at La Carreta restaurant in Hialeah.

Gimenez and Hernandez held a joint, private event in the city Thursday night with several hundred mostly older, Cuban-American voters -– who left the Royal Palace Ballrooms carrying Gimenez paper fans.

The endorsement is significant for Gimenez, who narrowly defeated Robaina last summer without winning the majority of the coveted Hispanic vote. While Gimenez’s support was broader, Robaina maintained a stronghold over working-class Hialeah and the neighboring cities of Medley, Hialeah Gardens and Miami Lakes.

Robaina has not backed anyone in the current race between Gimenez, County Commission Chairman Joe Martinez and five other, lesser-known candidates. But Hernandez’s endorsement will likely be taken as a sign that Robaina is at least not opposed to Gimenez’s reelection.

Some Hernandez supporters may still be a little resistant to backing Gimenez, however. Many city voters have not forgotten a mysterious robocall during last year’s mayoral contest that bashed Robaina and trashed Hialeah politics. Gimenez denied involvement, but Robaina blamed Gimenez’s campaign.

Hernandez succeeded Robaina as mayor last year, running for the post with Robaina’s blessing after Robaina stepped down to run for county mayor. In his race last fall, Hernandez, a shrewd populist, showed his political strength when he trounced former Hialeah Mayor Raul Martinez, who had never lost an election in Hialeah. (Raul Martinez and Joe Martinez are not related.)

By late last year, Gimenez had won over other political players who had backed Robaina, including former Gov. Jeb Bush, former U.S. Rep. Lincoln Diaz-Balart and Republican fundraiser Jorge Arrizurieta -– all of whom held a fundraiser for the mayor at the Biltmore Hotel in Coral Gables.

For Joe Martinez, the Hernandez endorsement could carry a particular sting because the two men share a political link: consultant Sasha Tirador, who ran Hernandez’s campaign last year and is leading Martinez’s operation this year.

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