“Governor Romney is at the top of the ticket,” Kevin Madden, a senior Romney adviser, said Sunday, seeking to make clear that his decisions would drive the policy debate. “Governor Romney’s vision for the country is something that Congressman Ryan supports.”

The choice of Mr. Ryan was intended by Mr. Romney and his aides to change the trajectory of the race after months of attacks from the White House and pressure from conservatives to raise the stakes of the campaign by embracing a bolder agenda for reducing the size and the role of government.

As the pair appeared before enthusiastic crowds on their second day together, Mr. Romney presented Mr. Ryan as a bipartisan conciliator in Washington and a man with ideas who works with Democrats on problems. It is at odds with how Democrats in Congress describe Mr. Ryan, whom they like personally but whose views they characterize as extreme.

But in the interview on “60 Minutes,” Mr. Ryan, 42, introduced himself as a patriot committed to turning around the country’s fiscal challenges. “We’ve dedicated much of our lives to saving this country,” Mr. Ryan said when asked about bursting onto the national stage.

When he arrived at a homecoming rally here on Sunday evening, Mr. Ryan wiped away tears as he took the stage and looked out upon a sea of familiar faces in the crowd. “Hi, Mom,” he said, choking up as he pointed to friends and neighbors who hailed him as a proud son of Wisconsin.

Gov. Scott Walker of Wisconsin, a Republican who survived a divisive recall election in June in a fight over collective bargaining that has made him into something of a conservative icon, said Sunday that members of his party should not be worried if Mr. Romney does not fully embrace every aspect of Mr. Ryan’s budget, which has become a centerpiece of the party’s fiscal agenda.

“Mitt Romney will have his own plan, but he values someone who has the courage to take on the tough issues,” Mr. Walker said in an interview. “With Paul on the ticket, you have the credibility of knowing that Paul Ryan is not going to be a wallflower. He is going to be an active part of a Romney administration.”