The running mates clearly sensed that the stakes were higher than usual for their faceoff, and both played hardball throughout, frequently interrupting one another and challenging one another's assertions.
On television's split screens, Biden's body language — a montage of pained smiles, winces, head shakes and eye rolls — often screamed incredulity when Ryan was speaking.
"I know you're under a lot of duress to make up for lost ground," Ryan shot back at Biden at one point, "but I think people would be better served if we don't keep interrupting each other."
In one of the night's lighter moments, Ryan helpfully provided a translation of one of Biden's putdowns.
"This is a bunch of stuff," Biden said of Ryan's dismissive characterization of the president's Iran policy.
"What does that mean, a bunch of stuff?" asked moderator Martha Raddatz of ABC News.
"It's Irish," Ryan offered.
"It is," Biden agreed, to laughter from the audience. "We Irish call it malarkey."
At another point, Ryan used Biden's own history of gaffes to explain away Romney's much-criticized comment dismissing the 47 percent of Americans who pay no income taxes, a comment Biden brought up repeatedly after Obama had failed to mention it in his debate.
"I think the vice president very well knows that sometimes the words don't come out of your mouth the right way," Ryan said.
There were spirited exchanges on taxes, abortion, Medicare, Libya, and more. It may not have broken new ground, but the conversation gave viewers a clear illustration of the sharp choices before them come Election Day.
"In case you haven't noticed, we have strong disagreements," Biden said in his closing statement. And then he distilled the Democrats' campaign pitch into a simple bid to give anxious Americans "a little bit of peace of mind."
Ryan then spoke of the "big choice" in this election, and argued that Obama had had his chance and failed.
"This is not what a real recovery looks like," he said. "You deserve better."
For all the political back-and-forth during the past two months, the race essentially stands where it was in August, before the two national political conventions, with the two candidates running about even in national polls.
There's been no shortage of drama in between: the revelation of Romney's caught-on-tape comment about the 47 percent, Biden's remark that the middle class has been "buried" in the past four years, Obama's weak showing in the first debate, the ongoing tussle over the administration's handling of the attack that left four Americans dead in Benghazi, Libya, and more.
With turnout critical, both campaigns are devoting considerable energy to ensuring that supporters are registered to vote and taking advantage of the early voting options available in many states. Nearly a million Americans already have voted.
The Democrats' monthlong "gotta vote" bus tour will be in Milwaukee on Friday, just in time to rev up supporters for the opening of Wisconsin's early voting season on Monday.
And both sides are keeping up the push for campaign contributions to keep the battleground-state airwaves full of political ads. Within a few hours of the debate, Romney, Obama and Biden all emailed supporters asking for more cash.
Benac reported from Washington. Associated Press writers Nedra Pickler in Washington and John Flesher in Hudsonville, Mich., contributed to this report.
Follow Nancy Benac on Twitter: http://www.twitter.com/nbenac
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