Wisconsin GOP Sen. Ron Johnson endorsed presidential hopeful Mitt Romney on Sunday.
Johnson announced the endorsement on MSNBC’s "Meet the Press," according to a Sunday morning tweet from executive producer Betsy Fischer.
Johnson brings Tea Party support to Romney, who has battled perceptions by many GOP voters that he is insufficiently conservative.
The endorsement gives a boost to Romney in a state he has already predicted he will win. A loss in the Wisconsin primary could also deliver a knockout punch to GOP contender Rick Santorum’s presidential campaign, strategists have said.
Romney already holds a greater than two-to-one edge in the delegate count and is expected to sweep Tuesday’s primary contest. In addition to Wisconsin’s winner-take-all primary, Romney is expected to win in Maryland and Washington, D.C. — both contests where Santorum failed to make it on the ballot.
Santorum said on Fox News Sunday that he would stay in the primary no matter what happens in Wisconsin.