“Senator Bill NelsonBill NelsonSenate panel unveils aviation bill with consumer protections, drone fix Driverless cars speed onto political agenda Biden leaves options on table for another White House bid MORE’s approval ratings are under the politically-dangerous 50 percent mark because he supported ObamaCare, which cuts Medicare by $500 billion, raised taxes on businesses and rationed healthcare for over 800,000 seniors in Florida," commented Wilcox.

Fifty-one percent of Florida voters said they approve of the job Nelson is doing, but only 48 percent said he deserves a third term, according to the survey.

Like Nelson, President Obama also received 51 percent job approval. Republican Sen. Marco RubioMarco RubioElection hacking fears turn heat on Homeland Security Will Republicans stand up to the NRA's insurrection rhetoric? The Hill's Whip List: Senate ObamaCare repeal bill MORE (Fla.), meanwhile, received 49 percent general job approval.

The Democratic Senatorial Campaign Committee responded to the poll with a release noting that "Nelson [and] Obama" are "more popular than Rubio" in Florida.

Rubio's approval rating jumped to 78 percent among Republicans. Nelson, meanwhile, has 66 percent approval among Democrats.

The poll was conducted May 17-23, and has a margin of error of 2.8 points.