"This race won't be about him,” Democratic Rep. Patrick Murphy said.
He said Lt. Gov. Carlos Lopez-Cantera has "put in time and energy" to run for Senate.
Rubio has brushed off speculation that he'll reconsider running.
Sen. Corker is pressing for Rubio to run, despite public reservations from the Florida Republican.
Democrat Katie McGinty is trying to unseat incumbent Republican Sen. Pat Toomey.
"The real issue is security,” Robert Blaha said.
Democrats see Wisconsin as a prime opportunity to pick up a Senate seat.
Sen. Pat Toomey (R-Pa.) has missed more than 80 percent of hearings on the Senate Budget Committee since 2013, a...
The incumbent leads his challenger by 3 points.
The primary is June 7.