Sen. Marco Rubio, R-Fla., holds a commanding lead over Rep. Val Demings, D-Fla., in a Senate race to be decided in November, according to the nonpartisan Mason-Dixon survey.
Rubio leads Demings by 7 points in a state where President Joe Biden's approval rating has dropped to 40%, according to the latest Mason-Dixon poll, the Washington Examiner reported.
The senator holds a 49% to 42% edge overall, with 9% undecided.
Among independent registered voters, Rubio holds a 10-point lead, Mason-Dixon results found.
Florida, a key swing state, has leaned Republican since former President Donald Trump won there in 2016.
"Party registered voters appear to be dug in along partisan lines and recent elections suggest that pattern is likely to hold," a Mason-Dixon memo said, the Examiner reported.
"The key for Demings to pull off an upset will be the ability to attract more unaffiliated voters."
Mason-Dixon previously found that Gov. Ron DeSantis, R-Fla., led Democrat opponents and had a total of 61% of independent voters in Florida.
Rubio, 50, is seeking a third term. He ran for the GOP presidential nomination in 2016 and is considered a potential 2024 contender.
DeSantis and Sen. Rick Scott, R-Fla., also have been considered potential presidential nominee contenders, as has President Donald Trump, a Sunshine State resident.
Demings, 64, was first elected to the House in 2016. The Examiner said she was the preferred candidate to challenge Rubio among Democrat leaders.
Both candidates entered the year with big war chests. Rubio had $10.6 million, and Demings had $8.2 million.
Florida Democrats running in the midterms must contend with Biden's disapproval rating, which was 55% according to the Mason Dixon poll. That rating was higher among men and all voters 50 and older (59%), and among independents (61%).
Demings led Rubio with Blacks (82% to 7%), women (48% to 41%) and in blue Southeast Florida (53% to 40%).
The Mason-Dixon survey among registered voters was conducted Feb. 7-10 and had a margin of error of plus or minus 4 points.
Politico in September reported that Republicans appeared ready to claim more registered voters than Democrats in Florida for the first time in modern political history.