Some of the findings:

Forty-one percent of Americans think it’s possibly or definitely true that in 2001, President George W. Bush knew about the 9/11 attacks before they happened. Despite Trump’s having blamed Bush for the attacks, his supporters are actually less likely to think this is the case than are Clinton’s supporters. Bush was, after all, a Republican.

The same percentage thinks that President Obama may be “hiding important information about his background” — shorthand for birtherism. More than two-thirds of Trump supporters believe this is possible, as do one-fifth of all Democrats.

More than 7-in-10 poll respondents think Trump may be withholding his tax information because it shows political or business links to Russia. That includes almost half of Trump supporters. This was the most widely accepted rumor, with 85 percent of Democrats thinking it may be true — 29 percent of whom feeling certain it was.

More than 6-in-10 thought that Clinton may have known about the Benghazi attacks in advance and let them happen. That includes 90 percent of Trump supporters, more than half of whom say it’s definitely true.