Yes, these are Democrats. And Iowa Democrats, as we've learned over the past decade or so, are on the liberal side of the ledger. So if anyone was going to rally to Clinton's side against the perceived attacks of Republicans and the mainstream media, it's true believers like the ones tested in the DMR poll.
Still, the fact that there is a widespread belief that things like the private e-mail server or the donors to the Clinton Foundation are trumped up is extremely good news for Clinton.
The key for Clinton — in both the primary and, to a certain extent, the general election — is to rally Democrats, especially liberal Democrats, to her cause. In the early days of her presidential campaign, she has staked out decidedly liberal positions on hot-button issues such as immigration and income inequality. But often, the best way to convince people you are one of them is to come under attack from enemies of those people. (Enemy of my enemy and all that.) And Republicans and, increasingly, the media, are very much enemies in the eyes of dyed-in-the-wool liberals.
If liberals — like those in Iowa — continue to see stories about the e-mail server and the Clinton Foundation as part of a broader witch hunt against Clinton being organized by her political enemies and reporters with an ax to grind, that's a best-case scenario for the former secretary of state. Why? Because with every report on her e-mails or her donors, it affirms the sense within her liberal base that she's being unfairly maligned. The more the merrier, from Clinton's point of view.
The alternate reality is that these scads of stories raise doubts about Clinton's ability to win next November, and, as a result, people begin to shop for a different candidate. While there is some evidence that Democratic voters are slightly worried about that possibility (four in 10 Democrats in the DMR poll say that keeping a private e-mail server will hurt Clinton in the general election), they remain largely united behind her.
The more Clinton can turn the negative storylines around her into an "us versus them" (no matter who the "them" really entails) conversation, the better for her chances.