Sen. Susan Collins talks with reporters on Capitol Hill, September 17, 2018. (Mike Segar/Reuters)

Michael Tomasky is getting ahead of himself:

Right now, four Republican incumbents in swing (or swing-ish) states face competitive races: Martha McSally in Arizona, Cory Gardner in Colorado, Susan Collins in Maine and Thom Tillis in North Carolina. . . . Logic tells us that politically, they’ll want to vote to convict, with the probable exception of Mr. Tillis. For a Republican in a state where Mr. Trump isn’t popular, convict is a much safer vote than acquit.

Maybe convict will be a safer vote in those states — but we don’t know that yet. Whether the people in a senator’s state who want a conviction outnumber the people who want an acquittal isn’t the only relevant political datum. Let’s say that it comes time to vote and significantly more Arizonans are anti-Trump than pro-Trump — but the anti-Trump voters are almost all not going to vote for McSally regardless of what she does, while the pro-Trump voters will almost all vote for her unless she votes to convict. In that case, acquittal is the safer vote.

[A] simple majority can vote to dismiss the articles without a trial. Mr. McConnell would face tremendous pressure from Mr. Trump and his amen corner to do just that. How would the four vulnerable Republicans vote on that motion?

Again, it could play out that way. Or Trump and his allies could decide that a trial that lets Republicans make a case against a witch hunt will work in their favor, and McConnell won’t face so much pressure. Hard as it is for my fellow op-ed writers, we’re just going to have to wait to see what happens.