Next, now, your voice, your vote, and a new face out on the campaign trail, the president's team calls her its secret weapon. Michelle obama. And abc's david muir has more tonight. David? Reporter:... See More
Next, now, your voice, your vote, and a new face out on the campaign trail, the president's team calls her its secret weapon. Michelle obama. And abc's david muir has more tonight. David? Reporter: Hey there, diane. Great to see you from the battleground state of ohio. Here, mitt romney's running mate is set to be the headliner. But this evening for president obama, it was his other running mate stealing the show. Reporter: It was the first time first lady joined her husband in iowa this campaign -- a state president obama won four years ago, and a state they're determined to hold on to. Your president knows what it means when a family struggles. This is not a hypothetical situation for him. He knows what it means to want something better for your kids and your grandkids. Reporter: The first lady also telling the crowd she was aware of where her husband had been and what he'd be eating here at the iowa state fair. Did you have a fried twinkie? Pork chop and beer. He's so pleased with himself. Reporter: Meantime, tonight, with mitt romney headed to a fund-raiser in north carolina, it is paul ryan here in ohio. And while rinl might be the running mate, it's his record driving much of the debate right now. Ryan's budget, with deep cuts he argues are needed, and big changes to medicare, eventually adding like a voucher-like system for seniors to shop for their own health care. But when pressed for specifics, ryan, trying to make it clear who is on top of the ticket. You -- how much? The point -- I joined the romney ticket. Reporter: But ryan isn't the only one being asked about his record. Romney was asked today, are you running on your budget or paul ryan's? I'm tone running for president. Can you tell us how your budget is difrment? We're very much on the same page. Reporter: Tonight, the battleground of ohio, where today, "world news" wanted to hear your voice. Talking to ohio voters, paul ryan riling some here, reinvigorating others. The voucher thing that he's talking about, I don't understand it. I like to see paul ryan and barack obama debate and leave romney and biden to duke it out after that. I feel like they both are in a different class. Reporter: They're going to love hearing that. To be honest with you, the romney campaign probably wouldn't mind hearing that tonight. They are reveling in the swelling crowds for paul ryan, the star pow earl he's helped bring to this ticket. But the star power in iowa today, michelle obama. The first lady hoping to help her husband carry that state again in november.
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