First off, what qualifies someone to be President? Years of government service? Governorship of a state? A stellar military record? Or is it just the individual? Not to be snarky, because if Hillary had won I would've happily supported her, but what were her unique qualifications? From the moment she carpetbagged her way to NY I knew she was running for the White House. But I figured that was fine, Bobby Kennedy did it. Has she spend that many more years in the senate than Obama? And how long was JFK in the senate before he ran? And before that? She was First Lady. Is that a qualification? It would certainly be a first. 35 years experience? C'mon, that was campaign hype, but it didn't matter to me because I knew she was smart. Ok, ambitious, but what politician isn't? And she's tough. Frankly, there are times I think Obama should've chosen her and made the ticket sexier, and more of a juggernaut. But then McCain would've chosen Mitt or someone like him and it would've been the two white guys against the chick and the black guy and they would've framed their attack differently.
Now, I'm far from a presidential historian but let's go back to the question: what qualifies someone to be President? Years of government service? By that measure, Strom Thurmond would've been sensational. Also gave us Bush I. Governor of a state? Reagan, Carter, and Clinton. Military record? Eisenhower. Ulysses Grant. Whether you think those were successful presidencies probably depends on your political stripes.
As for Obama himself. He's a lawyer. Editor of the Harvard Law Review and a professor of Constitutional Law. That makes him someone who has knowledge of and, in theory, respect for the law. (I think Nixon was a lawyer, so...) Obama also worked in the community when he could've cashed in that degree for Wall Street. Was he building his street cred or just doing good works? Years in the Illinois state senate, followed by his term in the U.S. senate. To me that makes him knowledgeable about how the system works which was eventually Lyndon Johnson's chief weapon as president, which helped him push through many JFK programs. But beyond that I think it's just the intelligence he demonstrates and compassion and basic human decency he exudes. It's beyond simple eloquence. I believe he is a person of his word. All of which, after the last 8 years is a refreshing change.
Which takes me to one last point: maybe it's just the right person for the times. Eisenhower fit the 50s post-war boom. Though one might question his choice of VP. Some presidents unite, as Roosevelt did in his time. Others, like Nixon, stir flames of discontent and divide. Again, a piss poor VP choice. Ford. Right man to heal the wounds of Watergate. A decent guy, so it seemed. Carter, again a Nixon backlash, and someone who still doesn't get the credit he deserves, at least for the Camp David Accords and trying to heal the Middle East. It takes a statesman to look beyond present hostilities and try to do the unthinkable to solve a fundamental problem. Reagan? A joke or the man who ended the Cold War, depending on your pov. Clinton? No national experience but, other than the obvious, an intelligent, forceful leader. The last 8 years have sucked the blood out of the country. I think Obama is a healer.
In short, that's why I support him. I don't think there's a model resume for the job. It's a combination of background, education, intelligence, grasp of the issues, vision, ability to communicate, toughness, compassion, honesty, and basic human decency. To me, those are his qualifications that go beyond the number of years he's been in the senate or the specific bi-partisan bills he's drafted or supported. By that measure, I think he could be a great president. And by the same measure, McCain would be 8 more years of disaster.
And, finally, a related afterthought: Could you imagine the campaign Rove and Company would have run if they were campaigning against an 8-year Democratic incumbent with the Bush record? It would've been like a school of Piranha devouring a pig... with lipstick.