So where does this leave us, and what lies ahead politically?
The big spoiler alert here is that President Donald Trump is not going to be removed from office, barring some kind of major new revelation. But that doesn't mean the whole thing doesn't matter. As the 2016 election showed us, even a slight shift in the electorate that could result from the impeachment proceedings could change who our next president is.
If impeachment helps Democrats move the needle by a couple of points with swing voters, that makes Trump's already-difficult re-election math significantly more so; if Republicans can convince Trump's base that this was yet another overzealous Brett Kavanaugh-like hatchet job, maybe that gives Trump a much-needed turnout edge. Part of what will determine that is the actual votes. Democrats have designs on getting at least one or two Senate Republicans to vote to remove Trump, but there seems to be a real chance that Democrats lose some of their own members in both the House and the Senate, while Republicans stay united in both.
Senate Majority Leader Mitch McConnell, R-Ky., is so confident of the latter that he is predicting as much. Asked Thursday by Fox News' Sean Hannity whether there would be any Senate GOP defections, he said, "I doubt it." As for the House, he was outright predicting at least a couple of Democratic defections and yet more GOP unity. "It looks to me over in the House the Republicans seem to be solid, and the Democrats seem to be divided," he said.
Calling one or two Democratic defections "divided" is certainly overstating it, but it seems likely the party will at least be more divided than the GOP.
We've already had two House Democrats vote against formalizing the inquiry - Reps. Collin C. Peterson, D-Minn., and Jeff Van Drew, D-N.J. - and Democrats are putting out word that other vulnerable and moderate Democrats could also vote no on impeachment. According to The Washington Post's whip count, more than five dozen Democrats have yet to commit. By contrast, only one Republican - retiring Rep. Francis Rooney, R-Fla. - has even left open the possibility of voting for impeachment.
In the Senate, it's conventional wisdom that the most likely GOP votes for removal would be from Sens. Mitt Romney of Utah, Lisa Murkowski of Alaska and Susan Collins of Maine, the last of whom is up for re-election next year.
I'm increasingly skeptical any of them will vote for removal, though. Removal is a higher bar than impeachment, for one thing. And it's not difficult to see how the likes of Romney and Collins would defend voting to acquit. It could be something to the effect of: "What the president did was wrong, but removal from office has never happened before. Democrats haven't even accused Trump of a crime, and the evidence didn't directly implicate him in the Ukraine quid pro quo."
On the Democratic side, you've got Sens. Joe Manchin III of West Virginia and Doug Jones of Alabama, who both come from very pro-Trump states and the latter of whom faces a re-election campaign. And if there's one state that could sum up how this turns out, it might be Arizona. Democrats should be hopeful of picking off Sen. Martha McSally, R-Ariz., in what is an election year for her, but the more likely crossover vote might be from Democratic Sen. Kyrsten Sinema.
So let's game this out. Say Republicans stay in lockstep with Trump, but six to 10 House Democrats and two Senate Democrats cross over. Suddenly, this becomes something the Democrats weren't even united on - something that was deemed to be too drastic for some of their most vulnerable members.
That may not be terribly surprising, given the severity of the punishment involved, but it would certainly be viewed as a less-than-ideal outcome for the Democrats. It becomes easier for Trump to argue this was an overcooked idea if it's too much even for several Democrats.
I've been skeptical from the start that impeachment would backfire on Democrats, and I don't necessarily think these defections would mean that would be the case. This will all be wrapped up more than nine months before the 2020 general election, which is a long time for people to forget about it or focus on other things.
But there was certainly a reason party leaders hesitated - whether because they didn't want to mess up their already-good chances or because they really did worry it could hurt them. It took them a long time to commit.
Since then, they've decided to go with a shorter process and opted not to try to get more key witnesses like former national security adviser John Bolton or more documents via court cases. They've decided not to accuse Trump of statutory crimes like bribery and obstruction of justice (that latter of which would revive the Mueller investigation's findings). They've said they had to move forward quickly not because of the looming election or any other practical political reasons, but because they worry that Trump will continue this behavior if he isn't held in check.
But what message will Trump take away from this if not even Democrats are united behind the idea that what he did was impeachable and worthy of removal from office? It's a dicey set of circumstances for a party whose leaders had resisted impeachment for so long, and there are no guarantees that their decision to relent will work out for the better.
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