Polling conducted by Civis Analytics for Senate Majority PAC, a Democratic super PAC, shows Murphy in a statistical dead heat with Rubio. He has 45 percent support compared to Rubio’s 44 percent; 9 percent of voters are undecided.

Civis’s modeling shows undecided voters are more likely to break toward Murphy, projecting him to win with 51.6 percent of the vote.
The poll surveyed 1,436 likely voters in Florida Aug. 9-Aug. 15, more than two weeks before both candidates cruised to victory in their respective primaries last Tuesday.

Recent public polls show Rubio with a comfortable lead, however. An average of six surveys conducted in the month of August shows Rubio with a 5.7-point lead, according to Real Clear Politics.