The Florida Supreme Court refused on Thursday to step into a challenge to a new map of the state’s 28 congressional districts approved by the Republican State Legislature, paving the way for November elections to be based on districts that a lower court said diluted the voting power of Black residents in violation of the State Constitution.
The court’s two-sentence denial said it was premature for the justices to intervene in a suit seeking to overturn the congressional map because the case had not yet wound its way through the state court system, which could take months or years.
The new House map, personally ordered by Gov. Ron DeSantis, a Republican, dismantles a House district held by Representative Al Lawson, an African American Democrat, and strongly boosts Republican odds of capturing other competitive House seats.
Former President Donald J. Trump carried Florida by 3.3 percentage points in the 2020 election, a close vote. Yet in the new map, Mr. Trump was favored by a majority of voters in 20 of the 28 districts, while voters in the remaining eight favored President Joseph R. Biden Jr.
Voting rights groups argued that the map ignored an amendment to the State Constitution approved by voters in 2010 that outlawed partisan mapmaking and specifically barred the creation of districts that diminished the ability of minority voters to elect their chosen candidates.
Mr. DeSantis contended that Mr. Lawson’s district was itself unconstitutional because it was drawn specifically to permit the election of a Black representative, taking in African American voters from across northern Florida who had little in common except their race.
A lower court blocked the Republican map from taking effect last month, substituting a map drawn by a Harvard University redistricting expert. The state’s First District Court of Appeals later lifted that stay, saying the judge had exceeded his authority. The Supreme Court ruling on Thursday rebuffed a request to overturn the appeals court’s decision.
“At this point, it seems hard to see congressional maps being upset for this November, especially given the Supreme Court’s repeated admonitions to federal courts to hold back on changes to election laws in the period close to the election,” said Richard L. Hasen, an election-law expert at the University of California, Irvine.