The question is whether this is a “be careful what you wish for” situation for House Dems. First, FiveThirtyEight:

According to the survey, 57 percent of Americans think it would be better if the upcoming trial included new witnesses who could potentially shed light on Trump’s conduct, while 39 percent said it would be better to keep the focus solely on the evidence introduced in the House hearings and included in the articles of impeachment, without calling new witnesses. Perhaps unsurprisingly, 65 percent of Democrats support calling new witnesses in the Senate trial. But 48 percent of Republicans also support calling new witnesses — although about the same number still want the trial to proceed with only the evidence introduced in the House hearings (50 percent).

Hmmm. YouGov is seeing similar results, right down to the surprisingly close split among GOPers on the issue.

On a subject as polarized as impeachment, you’d expect mirror-image effects in the Democratic and Republican numbers. If a heavy majority of Dems think new witnesses like John Bolton and Mick Mulvaney should be called, a heavy majority of Republicans might be expected to think that they shouldn’t. What explains the curious divide among Republicans here? It’s simple, I think — Trump himself has been eager to call additional witnesses and that’s confounding the usual partisan response on the right. Some righties are watching Schumer demand new witnesses and are instinctively answering, “Hell no.” Others are watching Trump demand that we finally hear from the whistleblower and Hunter Biden and are saying, “Hell yes.” If you strongly believe that the president is innocent and that this really has been a witch hunt cooked up Democrats and their intelligence allies to smear Trump, why would you care if Bolton and Mulvaney are called? That’s a small price to pay in return for the opportunity to put Biden on the stand and grill him about Burisma and his father’s influence in Ukraine with the whole country watching.

McConnell hates that idea because the more new witnesses there are, the less predictable the trial becomes. Acquittal is easy right now, based on the available evidence. If, however, Bolton ends up testifying that Trump told him to his face that he wanted Ukraine’s help to sink Biden’s chances at winning the 2020 election, acquittal would be … less easy, which means life for swing-state Republicans who are up for reelection next year would be less easy too. McConnell wants the vote to be easy. Trump, on the other hand, doesn’t care how hard it is. He knows acquittal is assured, whatever that may mean to Susan Collins and Cory Gardner. He wants a crack at real vindication, and that can only happen if the defense gets to call witnesses.

If Pelosi and Schumer are serious about pressuring McConnell to call Mulvaney and Bolton and not just posturing (spoiler: they’re just posturing), the way forward is clear. They should publicly offer Trump a compromise in which they’ll agree to support having Hunter Biden and the whistleblower testify in return for Trump letting Bolton, Mulvaney, and a few others testify too. It’s time to horse-trade. Trump might lunge at the offer, putting McConnell in the excruciating position of having to defy the president and his base. But it’s a hard offer for Democrats to make since they’d be opening themselves up to the charge that they’ve betrayed the whistleblower by exposing him to public retaliation and they’d be complicating Joe Biden’s presidential candidacy by tacitly endorsing the possibility that he did something nefarious with Ukraine that requires clarification from Hunter. If Biden were an also-ran in the presidential race or a radical whom Dems would prefer to see marginalized, that wouldn’t be so difficult. But he’s the establishment’s guy, the one man who can beat Trump. If they support putting Hunter Biden on the stand, they’ll have helped Trump achieve the very thing he sought from Ukraine, undermining Joe Biden’s electoral chances by impugning his integrity.

So Dems can’t offer this compromise. And because they can’t, they know McConnell’s under zero pressure to make a deal with them. If they won’t agree to let Trump call his witnesses, Republicans won’t agree to let Democrats call theirs. The safe play for Pelosi and Schumer, knowing that acquittal is assured no matter what, is simply to whine ineffectually that Bolton and Mulvaney should be called and hope that that whining ends up convincing the public that the eventual acquittal is a sham. And that’s just what they’ll do.