I don’t believe a vice presidential debate has ever influenced the outcome of an election. The most consequential ones have, however, stopped the bleeding afterthe presidential candidate flopped in his first debate.
Vice President Cheney’s performance against John Edwards in 2004 is the best example. But one could also cite George H.W. Bush in 1984 (against Geraldine Ferraro) and perhaps Joe Biden in 2012 (against Paul Ryan).
Donald Trump flopped in the first presidential debate, as well as in the aftermath. He will be hoping that Mike Pence can stop the bleeding.
Pence should have an excellent opportunity to do so. There’s a good chance that the moderator will press Pence as to how he, a principled conservative, can run with Trump whose positions often are (or have been) moderate or liberal. And Kaine will almost certainly press Pence as to how, in effect, someone so decent can defend Trump’s indecencies.
These lines of attack — purporting to praise Pence at the expense of Trump — won’t be easy to deal with. But if Pence succeeds in defending Trump, he should help repair some of the damage the Republican nominee has suffered lately.
Pence seems like the quintessentially nice and decent guy. If he persuasively vouches for Trump, it may well help the ticket.
Keep in mind, though, that Cheney, Bush, and Biden only set the stage for the comebacks of W, Reagan, and Obama. If these candidates hadn’t rallied in their second debate, the performance of their running mate would not have mattered.
Trump may improve in his upcoming debates, but I don’t expect him fully to cure the problems that plagued him in the first one. The moderators and Hillary know how to wind him up, and he seems temperamentally incapable of handling not taking the bait at some points during the course of an hour and a half (or thereafter).
However, if we do get back-to-back quality performances from Pence and Trump, the relatively small, but still consequential lead Clinton has opened up may all but disappear.