Follow along minute by minute on our website. But it's the big night of the big finish in tampa. Mitt romney in the final stretch, just hours from now, he will make his case to millions of americans,... See More
Follow along minute by minute on our website. But it's the big night of the big finish in tampa. Mitt romney in the final stretch, just hours from now, he will make his case to millions of americans, 68 days to go before your voice your vote. Earlier today he took the stage to rehearse. He also posed for pictures along with vice presidential candidate paul ryan and that's the staff behind him. And remember all those balloons that we told you about, well, 120,000 of them, we're told, are going to be dropping in three different stages from the air tonight. Beneath them will be abc's david muir on the floor of the convention hall. Good evening again to you here in tampa. To give the viewers at home the idea of the balloons you speak up, point the camera up, you can see them hanging there, waiting there to be unleashed. But the big change this evening, just the size of the stage. Mitt romney backstage this afternoon, saying he looks forward to reintroducing himself, defining himself to the american people. Reporter: Literally setting the stage here in tampa -- expanding it for the man about to make his case for the presidency. Today here, making adjustments to the teleprompter, getting his bearings on stage before the biggest speech of his life. Looking to convince american voters he understands their concerns, while offering a window into himself. He's had help making that case. His wife, ann romney, reaching out to women. I love you women! Reporter: Arguing her husband does understand. High nervously watched his wife from backstage as she defended him. I can tell you, mitt romney was not handed success. He built it. Reporter: Then, helping to make the case -- paul ryan. The first vice presidential candidate from the post baby boom generation, just 42. Romney watching ryan -- while his own grandchildren crawled over him. As ryan tried to reach a new generation for romney. College graduates should not HAVE TO LIVE OUT THEIR 20s IN Their childhood bedrooms, staring up at fading obama posters and wondering when they can move out and get going with life. Reporter: There were many others too, condoleezza rice and mike huckabee who made the case, saying this when it comes to romney's mmon faith. I care far less as to where mitt romney takes his family to church than I do about where he takes this country. Reporter: But tonight here, it is mitt romney's turn to make the case for himself. Revising the speech for weeks now on his ipad, he carries it at his side on the campaign. And one more clue about what's to come tonight, the music playing late today in the convention hall. ♪ Reporter: Giving away the secret guest. You hear the good, bad, the ugly. Pretty good suspicion it will be clint eastwood showing up here tonight. A source telling abc news that's the case. The romney ram pain want people to tune in to find out. Everyone waiting for mitt romney to take the stage and as he said this afternoon, getting a chance to introduce himself to the american people. All right. Collecting clues about clint eastwood tonight. Thank you. Last night's big event was the
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