I find myself constantly torn between an immovable object and an irresistible force in trying to size up this Senate race. The immovable object is my sense that Collins will be the toughest purple-state senator for Democrats to dislodge, partly because she’s been in office for so long and partly because she’s taken such care to cultivate her brand as a centrist. It paid off for her too: She consistently runs a few points ahead of Trump in Mane polling this year, proof that she’s picking up some Biden voters. It’s one thing for Dems to oust a first-term incumbent like Cory Gardner or Joni Ernst. But Susan Collins?

The irresistible force is that the polls are what they are and the national dynamic is what it is. Maine is a blue state and Biden is a stronger candidate than Hillary Clinton was. And the contest between Collins and Democrat Sara Gideon has been remarkably stable for months. In mid-July a Colby College poll found Gideon up five. A Bangor Daily News poll a few weeks later had Gideon ahead by … five. Last week’s NYT/Siena poll? Gideon by five. (A Quinnipiac poll published around the same time found Gideon up 12. That’s the one outlier.)

I gave away the result in today’s new Suffolk poll in my headline but you could have guessed. What makes Suffolk’s result noteworthy is that the poll was conducted from Thursday through Sunday, after Ruth Bader Ginsburg died and Collins announced that she thinks the next president should fill Ginsburg’s seat. If anything might upend this race, it’s a thermonuclear SCOTUS battle coupled with Collins trying to maneuver her way between furious Democrats and furious Republicans, right? Nope:

Note the bit at the end. Maine uses a ranked-choice system in which voters are asked to list their first and second choices; if your first choice doesn’t end up among the top two candidates, your vote automatically goes to your second choice. Gideon’s five-point lead would actually expand to something like seven in that case.

This race had been rated a toss-up by Larry Sabato’s Crystal Ball. Not anymore. It’s now “lean Democrat.”

Of 16 publicly-released polls of the race that have come out this year (as compiled by FiveThirtyEight’s database) from nonpartisan, Democratic, and Republican sources, Collins has only led in a single one, a Republican internal poll conducted in mid-June. Collins led 45%-38% in that survey. A few others have shown Gideon up only a point. But notice that even in this GOP internal, the longtime incumbent Collins was at just 45% of the vote. Across the 16 polls this year, her average support on the ballot has been just 42%. That is not a strong number for an incumbent who surpassed 60% in her last two reelection bids.

Collins’s best result in any public poll this year is just 44 percent. There’s no obvious reason — except SCOTUS fallout, maybe — to think she’ll suddenly break through that in the final weeks of the race, especially since late deciders typically support challengers, not incumbents. The irresistible force seems to be moving the immovable object.

I think she made the only play she could make on replacing Ginsburg. Any position other than letting the next president fill the seat would have incensed Maine’s Democratic voters, even above and beyond her votes on Kavanaugh and impeachment. It would have cost her most or all of those Biden crossover voters she’s holding onto right now. Whereas she has enough goodwill banked with Republicans from Kavanaugh and impeachment that she can afford to disappoint this time — with the important caveat that if Trump wins and the Senate stays red, they’ll get Amy Coney Barrett confirmed regardless. That is, as much as Maine Republicans may want her to confirm Barrett before the election, and as angry as they may be at her for refusing to do so, reelecting her is their ticket to making it happen. Ironically, and cleverly, by refusing to do what they want her to do, she makes the case for reelecting her that much more urgent to her base.

But that’s what makes today’s polling result significant. The RBG news came on the second night of the survey; Collins’s decision to let the next president fill the seat followed on Saturday. Even so, Suffolk finds Gideon’s lead stable at five. Considering how intense partisan polarization is right now, driven largely by feelings about Trump, maybe we’re all overestimating the effect of a Ginsburg vacancy on voter preferences. If a global pandemic couldn’t do much to fundamentally alter the polling between Biden and Trump circa March, maybe a Supreme Court battle can’t do it either. Maybe Collins is cooked no matter what happens now.

Free advice for Republicans, though: Since confirming Barrett *may* come down to whether Collins retains her seat in Maine, the “fill that seat” crowd should be careful not to give Maine Republicans more reason to be pissed off at her. I don’t know what the Judicial Crisis Network is thinking running ads in Maine knowing that Collins is already in deep trouble due to lack of Democratic support, and I really don’t know what Trump is doing badmouthing her on “Fox & Friends.” This is a moment to shrug at Collins’s reluctance to fill the seat and pressure Maine’s righty voters to support her anyway. This doesn’t help.