First things first: Vice presidential debates don’t really matter. The half-life of Thursday’s debate between Joe Biden and Paul Ryan will be exactly four days -- until next week’s rematch between President Obama and Mitt Romney.

And given the wonkiness of the debate -- from Libya to taxes to Afghanistan to Medicare -- the television image that will be repeated most often will be Biden’s sardonic grin, which sometimes seemed out of place, especially when the subject was foreign policy. That’s an easier “controversy” for news shows to hash over than the dense material of a substantive policy discussion.

Still, Biden had one mission, and he accomplished it: to stanch the Democrats’ near-panic after Obama’s lackluster performance in Denver last week. With a steady diet of old-fashioned Democratic talking points, the vice president did just that. It wasn’t subtle; he brought up Romney’s dismissal of 47% of the American public as moochers no fewer than four times. For the liberal base, Biden’s traditional defenses of Medicare, Social Security and taxing the rich were pure catnip. For undecided voters, they may have been less convincing.

DEBATE LOG: Vice Presidential Debate


Ryan’s job was easier; all he needed to do was navigate 90 minutes without putting his foot wrong or disagreeing with his own nominee. By that benchmark, Ryan succeeded too. It’s possible to flyspeck his performance on a couple of counts: He seemed to distance himself from Romney’s call for a defense budget increase, for example. And he may have bought the GOP some trouble with undecided women by stating bluntly that a Romney administration would “oppose abortion.” But that’s a far clearer position than Romney’s awkward statement to the Des Moines Register that he wouldn’t pursue any legislation to that end.

Who won? I’m going to call it a draw. Both candidates made their points, effectively. An instant poll by CNN gave Ryan the edge among registered voters, 48% to 44%. Another instant poll by CBS gave Biden a win among uncommitted voters, 50% to 31%.

But since this debate was essentially a sideshow, the winner -- on points -- was the Obama campaign. Biden stopped the downhill slide, at least in terms of internal morale. And he may have given his boss a lesson or two on how to go on the attack.

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Follow Doyle McManus on Twitter @DoyleMcManus