The incumbent Republican senator leads by just two points, 49-47, among likely Florida voters.
This latest poll indicates Murphy is moving closer to Rubio since Quinnipiac last polled Florida in September. The previous poll showed Rubio +4, while the latest from Quinnipiac shows Rubio +2.
In mid-September, Rubio led by as much as nine points, according to a Suffolk University poll of the Sunshine state.
The Quinnipiac University poll was conducted via live telephone interview from Oct. 10-16 among 660 likely Florida voters, with a margin of error of plus or minus 3.8 percent.
TPM's PollTracker Average for the U.S. Senate race in Florida shows Rubio leading Murphy, 47.6 to 43.3.