A new poll from Pew Research Center and USA Today shows the danger. When respondents were asked to name in their own words the biggest negative for Clinton from her long career in public service, the most common response was Benghazi. Sure, it’s only 15 percent who gave that answer, but that’s still a lot.

And it’s not just Republicans; Democrats also picked it more often than anything else, with 8 percent listing the attack as Clinton’s biggest negative.

Just because Democrats believe there was nothing nefarious about Clinton’s role in Benghazi doesn’t mean there are no grounds from which to criticize her. Besides, they should have learned from ” a government takeover of health care” and ” you didn’t build that” that bumper-sticker slogans can still deliver blows. That’s politics.

Respondents to the Pew survey weren’t given a list of options to choose from, but had to volunteer their own answers — almost 20 percent couldn’t come up with any negative at all — and it’s not a good thing for Clinton that a plurality of voters had Benghazi on the top of their minds.