Joe Biden's performance as Barack Obama's running mate has been pretty predictable - even when unpredictable.
The biggest knock against Biden during discussions on whether he would make a good vice presidential nominee was that his mouth tends to get him in trouble. And it has, with Biden recently raising the expectation that Obama would be tested by an international crisis soon after taking office - a comment that Obama said showed Biden's penchant for "rhetorical flourish."
Republicans John McCain and Sarah Palin have used that comment to suggest that Obama is not prepared to deal with such a problem. That's not what Biden said - he argued Obama would persevere because he's "got steel in his spine." But McCain is using a recording of Biden's comments in a new ad against Obama.
"We're going to have an international crisis ... to test the mettle of this guy," Biden says in a recording replayed in the ad over grainy images of a woman crying and people rioting in the streets of a foreign land. "I guarantee you it's going to happen."
An announcer interjects: "It doesn't have to happen. Vote McCain."
But despite the occasional gaffe that's been highlighted, the Obama team says Biden has been a steady asset.
"Yes, there are those moments when you say, 'Wow, I wonder why he said that,'" said Obama adviser David Axelrod, but he added: "Even in the cold hard world of politics, you just look at his numbers. The American people have really embraced him and he's got a very favorable standing.
"So I don't care if every once in a while there's one of those cases where you sort of say, 'Geez, I'm not sure I would have said it just that way.' I don't care about that because at the end of the day, I think the upside is so great," Axelrod said in a telephone interview.
Since the party conventions, Biden's favorable ratings have steadily gone up. An Associated Press-Yahoo News poll conducted earlier this month found both Biden and Alaska Gov. Sarah Palin were viewed favorably by 48 percent of respondents, but his figure was up from 37 percent the previous month, while hers remained about the same as her earlier 47 percent. And her unfavorables were rising, from 28 percent to 39 percent, while his went from 30 percent to 33 percent.
Biden completed his 170th interview Friday night in two months, his staff said, while Palin has declined most interviews.