Since I’m discussing Democratic presidential candidates, I’ll offer my typical disclaimer that I’m currently leaning towards Warren. Anyway, last week Eric Alterman offered this as a reason to not support Sen. Bernie Sanders (boldface mine):
Sanders turned so negative toward Clinton that it hurt her in the general election. Even though he campaigned for her after he lost the nomination, roughly 12 percent of Sanders’s supporters switched to Trump, and enough of the rest supported Jill Stein’s kamikaze candidacy that it helped tip key states to Trump.
The problem is that a small fraction–with one exception–of losing primary supporters always switch parties (boldface mine):
For example, Schaffner tells NPR that around 12 percent of Republican primary voters (including 34 percent of Ohio Gov. John Kasich voters and 11 percent of Florida Sen. Marco Rubio voters) ended up voting for Clinton. And according to one 2008 study, around 25 percent of Clinton primary voters in that election ended up voting for Sen. John McCain, R-Ariz., in the general. (In addition, the data showed 13 percent of McCain primary voters ended up voting for Obama, and 9 percent of Obama voters ended up voting for McCain — perhaps signaling something that swayed voters between primaries and the general election, or some amount of error in the data, or both.)
Moreover, the Sanders to Trump voters weren’t likely to vote Democratic anyway. The reason I bring this up isn’t because someone is wrong on the internet (though it’s kind of shocking that it’s Alterman, whose Sound and Fury is a classic). Candidates should ‘go negative.’ Not over stupid stuff, but should Warren lay off Biden on his bankruptcy-related awfulness? Of course not. I’m sure others can think of similar examples. As long as we continue to think that negative campaigning is bad (and people really seem to have deep-sixed just how awful the 2008 Democratic primaries were), we’re not going to vet the nominee adequately.