Flash back to the week after the first presidential debate. Romney was widely believed to have triumphed over Obama in that forensic exhibition, due in large part to the president's disinterested showing. After more than a month of maintaining a solid lead over Romney in national polls, Obama's diffidence had caused his standing to plummet so badly that he was slightly behind in most surveys of the popular vote, as well as gradually losing his electoral college edge. Spirits were low among Democrats, in stark contrast to the euphoria that followed the lackluster Republican National Convention and the calamity of the "47 percent" tape.
By winning the vice presidential debate, Biden began the process of changing that.
Most of us don't remember it that way now. When people are asked about the cause of Obama's last-minute turnaround, Hurricane Sandy or the Democrats' broader demographic base are far more likely to come up as answers. Nevertheless, the data indisputably shows that before the Biden-Ryan debate, Romney was gaining political momentum at a steady clip. Viewers of the debate (the third most watched vice presidential debate in history) were much more likely to view Biden as having won (50% to 31% according to a CBS poll of uncommitted voters and 42% to 35% to a Reuters poll, with CNN only giving Ryan a 48% to 44% edge because it accidentally polled 8% more Republicans than the general population). After the debate, Romney's political momentum had been significantly slowed down, if not entirely halted.
The reason for this is simple. After watching Obama spend most of the first debate carefully avoid saying anything that might appear too bold or risky, voters were now treated to Biden's brazen pugnacity.
When Ryan tried to make political hay over the Benghazi attack, Biden disdainfully referred to his assertions as "a bunch of malarkey" before thoroughly deconstructing the flaws in that line of GOP criticism. He was similarly succinct in his condemnation of Ryan's claim that Obama had allowed Iran to get closer to developing a nuclear weapon, memorably summing up his objections with the declaration that "Facts matter." As Ryan launched into a boilerplate attack on Obama's stimulus legislation, Biden called out his hypocrisy by pointing to letters the Wisconsin Congressman had sent to the vice president personally asking for stimulus funds for his own constituents. Later, when Ryan tried to pass off his Medicare plan as bipartisan, Biden embarrassed him by refusing to let him ignore that not one prominent Democrat - including the Senator from Oregon and former Clinton budget director who initially helped him put it together - still supported Ryan's final proposal.
In short, Biden was willing to give as good as he got from Ryan, and nothing inspires Americans more than a sign that one of their political leaders has guts.
This isn't to overstate the importance of the Biden-Ryan debate or claim that it deserves primary credit for turning things around. Even the best vice presidential candidates haven't been able to carry elections when the top halves of their tickets were wanting, as Lloyd Bentsen famously learned when his trouncing of Dan Quayle in the 1988 vice presidential debate failed to translate into votes for Michael Dukakis. Nevertheless, Biden's victory was the key first step in restoring political vitality to a campaign that had seemed dangerously close to becoming moribund following Obama's performance in the first debate. It showed that Democrats had just as much as fight in them as Republicans, that as Franklin Roosevelt once declared (during his first re-election campaign in 1936), "never before in all our history have these forces [organized money] been so united against one candidate as they stand today. They are unanimous in their hate for me - and I welcome their hatred."
If Obama wants to fare well in the tough political battles that lie ahead of him over the next four years, he would be well-advised to follow the credo so perfectly articulated by Roosevelt - and so impressively displayed by Biden.