“Senator Bill NelsonBill NelsonBipartisan group demands answers on United incident Is Congress encroaching on Americans' Internet privacy? Trump's Labor pick endorsed by Hispanic lawyers 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 RubioTop Trump officials push border wall as government shutdown looms Rubio defends Trump: 'This whole flip-flop thing is a political thing' Rubio: Shutdown would have 'catastrophic impact' on global affairs 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.