I agree that if 50 Republicans vote for the nominee anyway, it doesn't make sense to punish red state Dems who latch onto a fait accompli. No Dem should be the deciding vote though.
As for Collins, while she says she won't use a "litmus test", she does want a candidate with good "judicial temperament" and a "respect for precedent".
That's code for "Wouldn't overturn Roe v. Wade"
That has literally never been code for "Wouldn't overturn Roe v. Wade" on any other nominee she's ever voted on. If the new judge is the fifth vote to dismantle Roe, Collins will have voted yes on four of those five (with Thomas predating her Senate tenure).
Barack Obama wrote:“The Democrats’ job is not to exaggerate; the Democrats’ job is not to simply mimic the tactics of the other side. All we have to do is work hard on behalf of that truth. And if we do, we’ll get better outcomes.”
Counterpoint: Obama spent eight years doing this and look where we are now.
Not that I think the Dems should "exaggerate" or lie -- and I don't think they need to, either. In a vacuum, if you strip away everybody's dumb tribal identities and all the bullshit, Dem policies are more popular than GOP policies. But they should absolutely "mimic the tactics" of the GOP in other respects, because the GOP has proven those tactics work. For instance, if by some miracle, the Dems retake the Senate (unlikely) before a new justice is confirmed (even more unlikely), they should blockade any nominee, just as McConnell did. If they retake the entire federal government in 2020, they should pack the court and admit DC and Puerto Rico as new states. They tried "when they go low, we go high," and it was an astonishing failure. It's time for them to try "when they take off the gloves, we put on the brass knuckles."