Back when Florida was the nation’s premier political battleground, Democrats in the state had hundreds of thousands more registered voters than Republicans and a fairly simple formula for competing in presidential contests: run up the score in key metro areas like Miami-Dade County, and try to manage losses in the vast rural and exurban areas that stretch from the Panhandle to the Everglades.

But a statewide surge in GOP voter registration gave Republicans an edge over Democrats for the first time and foreshadowed Gov. Ron DeSantis’ 19-point victory in November. Democrats are rapidly losing their advantage in Miami-Dade, perhaps their most important market in Florida.

Just in the last four years, the number of registered Democrats in the county decreased by over 6,000 voters, and their advantage over registered Republicans was almost cut in half, dropping from a 15-point lead in August 2019 to eight in July 2023, according to a Miami Herald analysis of state voter registration data. Democrats had around 138,000 more registered voters than Republicans in Miami-Dade.

The shift has Democrats concerned about the party’s ability to stay relevant in 2024, when voters will cast ballots in the presidential election and local races. Party leaders are scrambling to make changes.

“There’s no way for Democrats to win statewide in Florida by having a voter registration meltdown in Miami-Dade County,” said Fernand Amandi, managing partner of the Miami-based political strategy and polling firm Bendixen & Amandi. “Democrats are now registering as Republicans and Republicans are out-hustling Democrats in the most important county in the state for Democrats.”