Rep. Paul Ryan (R-Wis.) on Friday endorsed former Massachusetts governor Mitt Romney as the 2012 Republican presidential nominee.

The House budget chairman announced his endorsement on Fox News’ “Fox and Friends,” saying that while the contentious GOP primary process has “been constructive up until now,” it could soon become “counterproductive.”

House Budget Committee Chairman Paul Ryan (R-WI) joins other members of the House GOP leadership for a brief news media availability. (Chip Somodevilla/GETTY IMAGES)

Ryan added that, of the Republican presidential candidates, Romney “has the best chance of defeating Barack Obama in the fall.”

Wisconsin is holding its primary on Tuesday, but Ryan’s endorsement will resonates far outside his home state. Ryan, a proponent of deep cuts in entitlements and agency funding, has become the leading voice on debt and spending issues in the Republican party.

His blessing of Romney comes on the heels of endorsements from former Florida governor Jeb Bush, former president George H.W. Bush and Sen. Marco Rubio (R-Fla.)--clear signs that Republican leaders young and old, from both the tea party and establishment wings, are ready for this primary season to be over.

Ryan’s endorsement also comes a day after his budget, praised by Romney, passed the House. He told Fox News that he had “spent a good deal of time” discussing the country’s fiscal situation with Romney and liked what he heard.

“I am profoundly grateful to Congressman Ryan for his endorsement today,” Romney said in a statement after the announcement. “I am even more grateful for all the hard work he has done to help turn around our country and restore it to greatness.”

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