Last week, Mitt Romney won and Barack Obama lost. But the outcome was much more a matter of Obama losing than of Romney winning—because it was only Obama’s passive-unaggressive refusal to parry and thrust that permitted Romney to coast unmolested to victory on his perfectly prepared, professionally rehearsed, thoroughly focus-grouped, earnestly delivered speechlets.

This week was different. Joe Biden won, but not because Paul Ryan let him. Ryan came in second, you might say, but he didn’t lose.

Biden won because he bucked up his side. Democrats feel much, much better today than they did yesterday. Their weeklong freakout, their six-day funk, is in remission, masked by a huge sense of relief—mixed, however, with a slightly uncomfortable tingle of nervousness about next week, when it’ll be Obama’s turn again.

Biden did a lot better than I was expecting. I worried that he might bloviate unattractively. I fretted that he might wander off into irrelevant anecdotes and impenetrable riffs. He bloviated, all right, but not (to me, at least) all that unattractively. And he was astonishingly focussed and disciplined. His anecdotes and asides were to the point. His arguments were clear and easy to follow. Not once, I noticed, did his favorite adverb cross his lips. Maybe the internal mantra that kept him on track was “Don’t say ‘literally.’”

I’m sure that plenty of people were put off by the Vice-President’s facial antics—the patronizing grins, the mock exasperation, the silent giggles. I was a little put off myself, at first. But as he went along, he managed to earn a right to be what you might call cheerfully contemptuous.

Anyway, like other Obama-Biden supporters I talked to, I didn’t really mind the grins, etc., per se. I was just worried that they might alienate a lot of “undecided voters” and other weak-minded types. Which I reckon they did. But Biden is Biden, all of a piece. And I suspect that as many “undecideds” were attracted by his alpha-male macho—his domination of the conversation, his refusal to give an inch, his fighting spirit, his rapid-fire interjections (“That didn’t happen!”;“Not mathematically possible!”; “Martha, that’s a bizarre statement!”) as were repelled by his rough manners. Biden’s “rudeness” was probably a wash. But his substance was a winner.

One of the Vice-President’s best moments came after Ryan attacked him on the stimulus, accusing him of overseeing “ninety billion dollars in green pork to campaign contributors and special-interest groups.” Biden’s reply is worth lingering over:

BIDEN: I love my friend here. I—I’m not allowed to show letters, but go on our Web site. He sent me two letters saying, “By the way, can you send me some stimulus money for companies here in the state of Wisconsin?” We sent millions of dollars. You know… [crosstalk] MARTHA RADDATZ (moderator): You did ask for stimulus money, correct? BIDEN: Sure he did. By the way… RYAN: On two occasions we—we—we advocated for constituents who were applying for grants. That’s what we do. We do that for all constituents who are… [crosstalk] BIDEN: I love that. I love that. This was such a bad program and he writes me a letter saying—writes the Department of Energy a letter saying, “The reason we need this stimulus, it will create growth and jobs.” His words. And now he’s sitting here looking at me. And by the way, that program, again, investigated. What the Congress said was it was a model. Less than four-tenths of one per cent waste or fraud in the program. And all this talk about cronyism. They investigated and investigated, did not find one single piece of evidence. I wish he would just tell—be a little more candid.

Ryan’s attempt to cadge goodies for his constituents from a program he had voted against was a form of hypocrisy that is absolutely standard procedure on Capitol Hill. Biden, a four-decade denizen of the place, knows this, and he has surely done it himself many times. Even so, it was fair game for him to use Ryan’s foray into constituent service against him. But Biden could have chosen to point out the hypocrisy and leave it at that. Instead, he went further: he connected the policy dots. Ryan made those requests because, for people in his district and state, the stimulus would “create growth and jobs”—and if that was true in Wisconsin, which it was, it necessarily follows that the stimulus created jobs and growth in the nation as a whole.

Then there’s that last line, a fine, subtle flourish: I wish he would just tell—be a little more candid. The unspoken words “the truth” point to the unspoken word “lie” like a pool cue: a double bank shot, and Joe sinks it.

Biden was equally adept at filleting his opponent’s proposed tax cuts for the rich, his hedge-fund-friendly definition of “small business,” and his call for massive increases in defense spending. He found a way to complain about Republican obstructionism without sounding whiny or self-pitying. (“Just get out of the way! Stop talking about how you care about people! Show me something! Show me a policy! Show me a policy where you take responsibility!”) And in the exchange about abortion, he was the voice of ordinary Catholics—attached to the Church as to his own family, respectful of its doctrines on some personal level but implicitly reserving the right to make his own judgments while explicitly supporting the right of women to make theirs. Biden was like an understanding parish priest. Ryan was more like a callow seminarian eying an assignment on a Cardinal’s staff or a post in Rome.

Biden’s staccato interruptions made it hard for Ryan to develop coherent lines of argument, but Ryan, to his credit, didn’t complain about it. If he thought Biden was out of line, he didn’t show it. He made his points adequately. He stayed calm. He made no big mistakes. He committed no gaffes. He hung in there. He didn’t lose. It wasn’t because of him that Biden won. It was because of Biden.

See our full coverage of the debates.

Photograph by Scott Eells/Bloomberg/Getty.