In this video, NewsHour political analysts David Brooks of The New York Times and Mark Shields, a syndicated political columnist, discuss what Barack Obama needs to do at the Denver convention and review the recent political ad wars.

The first 4 minutes is spent on the vice presidential nomination, so you might want to skip to 4:30 in the time code when they start talking about Obama's challenges, and the recent round of negative ads following John McCain's gaff of not remembering how many houses he owns.

Convincing Hillary Clinton supporters to align with Obama will be a major challenge, Shields predicts, as will showing Obama's "log cabin" background and his rise to political stardom from a multi-cultural and humble upbringing.

What Obama offers is tomorrow versus yesterday. And it seems to me he's got to re-establish that theme. And the theme is: We're in a global world. We're in a multicultural world. The frameworks of the old world don't apply. I am the new framework." - David Brooks, New York Times Columnist

"We've elected plenty of rich guys to the White House, and some have been good and some have been bad. The people in the upper middle class are perpetually thinking people in the middle class are really angry at people in the super upper class. They're not. And they don't mind richness. And I don't think they're going to think John McCain is a rich, decadent guy." - David Brooks, New York Times Columnist

"All great revolutions are led by aristocrats, I think it's fair to say, Franklin Roosevelt being prime among them. But it isn't a question of whether he's rich. It's whether he understands what fellow citizens who aren't rich are going through. And I think that's really the problem that this raises for John McCain." - Mark Shields, Syndicated Columnist

"I think [negative ads] may demean Obama a little more, because they think he has a little more riding on the breaking through to some sort of new politics, but I think people are going to look at these two ads and say, "Dumb, dumb, dumb."" - David Brooks, New York Times Columnist

But the Clintons remain a psychodrama, and in particular Bill Clinton, and I think the Democrats are holding their breath and hoping that he can do what he did so well for himself in 1992, and that is to introduce, and make the case, and cast the election in the right terms. And there's probably nobody more better equipped to do it than Bill Clinton." - Mark Shields, Syndicated Columnist

1. What do you know about Barack Obama?
2. What are political conventions? Are you following the Democratic Convention in Denver?
3. What political challenges are Barack Obama and John McCain facing right now?

1. What did you think of the negative ads? Do you agree with David Brooks that Obama has more to lose with negative messages than McCain?
2. Is John McCain rich? Is Barack Obama rich? Does it matter if how much money a presidential candidate has? Why or why not?
3. What aspects of a candidate's upbringing, education and career are important to you? Why?
4. Do you think the Democrats will have a successful convention? What does success mean?