“This Quinnipiac University poll finds Sen. Marco Rubio in good shape when matched against his two potential Democratic opponents,” Brown added.

“None of the other Republican candidates for Sen. Rubio’s seat has a lead over either of the two Democrats, Congressmen Patrick Murphy and Alan Grayson. But if Rubio’s last-minute decision is to seek re-election, he could be in the driver’s seat.

“In general, this poll of the three major swing states, Florida, Ohio and Pennsylvania, is good news for the GOP. Sen. Rob Portman is in a dead heat with former Gov. Ted Strickland in Ohio. But that is an improvement for Portman, who earlier in the campaign was down as much as 9 points. And in Pennsylvania, GOP Sen. Pat Toomey has a 9-point lead. It is far too early to say he’s a sure thing, but he is in good shape.”