Washington (CNN) - Rep. Paul Ryan of Wisconsin endorsed Mitt Romney on Friday, ahead of his state's Tuesday primary.
The chairman of the House Budget Committee said Romney is the best person to serve as president and the candidate most likely to beat President Barack Obama in the general election.
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"I am convinced that Mitt Romney has the skills, the tenacity, the principles, the courage and the integrity to do what it takes to get America back on track," Ryan said on Fox News. "I believe he is the right person for the job."
He also called on conservatives to "coalesce" around the former Massachusetts governor.
"I think we're entering a phase where it could become counterproductive if this drags on much longer," Ryan said.
The announcement came four days before his state's GOP primary and one day after the budget he helped craft passed in the House.
A GOP source said the timing of the news is critical given Ryan recently wrapped up his stint as chair of the Republican National Committee presidential trust, which made it difficult for him to pick a horse in the 2012 election.
The Democratic National Committee sought to capitalize on the news with a memo and web video released Friday, titled "That's Amore" that tied the Republican frontrunner to the Ryan budget.
"The Romney-Ryan budget ends Medicare as we know it and helps big insurance companies while putting the guaranteed coverage seniors have earned and paid for at risk-in order to give a tax cut to the wealthiest few," DNC Communications Director Brad Woodhouse said in the memo.
"Romney owns these proposals," Woodhouse continued.
Romney has voiced consistent support for Ryan's proposals, which include plans to transform Medicare into a system in which the government subsidizes purchases of health insurance within the private market instead of paying medical bills directly.
The proposal would offer future seniors a choice of staying in the traditional plan or opting instead of a private plan, all of which would be available via a new Medicare exchange.
Republicans argue the reforms are necessary to curb costs and address the budget deficit, while Democrats say the changes will negatively impact vital national programs.
News of the endorsement was first reported by the political blog, BuzzFeed.
- CNN's Dana Bash, Jim Acosta, Paul Steinhauser and Shannon Travis contributed to this report.