"In Congress, when they take out the heavy books and wall charts about Medicare, my thoughts go back to a house on Garfield Street in Janesville. My wonderful grandma, Janet, had Alzheimer's and moved in with Mom and me. Though she felt lost at times, we did all the little things that made her feel loved," he said.
"We had help from Medicare, and it was there, just like it's there for my mom today. Medicare is a promise, and we will honor it. A Romney-Ryan administration will protect and strengthen Medicare, for my mom's generation, for my generation and for my kids and yours."
Posturing on Medicare, he said, would no longer work.
"Mitt Romney and I know the difference between protecting a program and raiding it. Ladies and gentlemen, our nation needs this debate. We want this debate. We will win this debate."
And he accused Obama of doing nothing in the face of the mounting debt.
"They have no answer to this simple reality: We need to stop spending money we don't have. ... And I'm going to level with you: We don't have that much time. But if we are serious and smart and we lead, we can do this."
Ryan also spoke warmly of Romney, praising his experience in business and with the Olympics and his tenure as governor of Massachusetts. But he had the audience laughing when he joked about their different iPod playlists.
"There are the songs on his iPod, which I've heard on the campaign bus and on many hotel elevators. He actually urged me to play some of these songs at campaign rallies. I said, 'I hope it's not a deal-breaker Mitt, but my playlist starts with AC/DC, and ends with Zeppelin,'" Ryan said.
But Ryan said that while they are different people from different backgrounds, he and Romney share a vision for the future and a commitment to face up to the nation's problems.
"We will not duck the tough issues, we will lead," he said. "We will not spend four years blaming others, we will take responsibility. We will not try to replace our founding principles, we will reapply our founding principles.
The work ahead will be hard. These times demand the best of us - all of us, but we can do this. Together, we can do this."