Also on Fox News, Sen. John McCain (R-Ariz.), with four years of distance from his own 2008 pursuit of the presidency, said a Vice President Ryan could be instrumental in shepherding the Romney agenda through Congress.
"Paul Ryan brings the balance of understanding how the Congress works ... [with] how the budget process works," McCain said, adding that Ryan's "established relationships ... will make him most effective in getting the Mitt Romney agenda through the Congress."
Ryan, elected to the House in 1999, became recognizable outside the Beltway in the 112th Congress, when he was tapped to serve as chairman of the House Budget Committee. From that perch he has been the main architect of what has come to be known as the "Ryan budget," a controversial fiscal blueprint that makes steep cuts across government spending.
Sen. Ron Johnson (R-Wis.) said the Ryan pick contrasts Romney's willingness to tackle the country's debt and deficit woes with Senate Democrats' failure to pass a budget for the past three years.
"Democrats refuse to put their fingerprints on any kind of game plan that the American people can actually take a look at and hold them accountable," Johnson said on CNN. "Paul Ryan is willing to do that. Mitt Romney is willing to do that."
Still, Romney's campaign tried to create some separation between the presumptive presidential nominee, who implemented nearly universal health care coverage in Massachusetts during his time as governor, and Ryan's controversial plan. Key talking points leaked to reporters Saturday said Romney would present his own budget plan and noted that the Romney and Ryan "aren't going to have the same view on every issue."
Priebus, when asked today whether Romney would adopt the Ryan budget, tried to toe the same line the campaign laid out a day earlier.
He said Romney "appreciates and admires the work Paul Ryan has done, but Mitt Romney has his own plans."
Republicans also sought to bring attention to Ryan's work with Sen. Ron Wyden (D-Ore.) on the Medicare plan, even as Democrats - including Wyden - sought to downplay the partnership.
Wyden and Ryan worked together in December 2011 to develop a paper outlining ways to provide for Medicare solvency, including a "premium support" model, under which Medicare would allow a menu of competing plans to offer coverage with government payments.
"[Wyden] has joined with Paul Ryan on the voluntary program for seniors [so] they could be responsible for their own health care," McCain pointed out. "That kind of proposal is something we need to carefully examine and pursue."
But Wasserman Schultz suggested this connection is disingenuous.
"Let's make sure everyone knows that Ron Wyden voted against the Ryan budget," she said. "Even Wyden agrees turning Medicare into a voucher program would be a bad idea."
But rather than defend Wyden, Axelrod distanced the Obama campaign from him.
"I just disagree with Sen. Wyden on this ... and so do most of the experts who have looked at this," Axelrod said, describing the plan as one that would put "Medicare in a death spiral" and "raise costs on seniors by thousands of dollars."
Niels Lesniewski and Emily Pierce contributed to this report.