I could see Murkowski following through, though at this very moment McConnell has her over a barrel on a priority of her own so he could put the squeeze on her. Sigh. (Wouldn't be the first time this congress he did that, either.)
Grassley... I honestly don't know.
Given the race I suspect Collins would resist until after the election, then readily vote (after said hemming and hawing) in the lame duck.
- Not listen to Biden's stupid fucking advice on trying to appease a death cult capitalist with Gorsuch and spend time on more productive things
Garland, but that was my fault initially for saying Gorsuch. Are you saying to not nominate anyone at all? The staff involved in it were probably specialized in vetting/etc. and so I'm not sure how much of substance that really would have saved.
- Hold a speech every day calling McConnell a criminal for not doing his job as Senate Leader
This conflicts with the above statement? Anyhoo, if he did this I bet most Americans would (unfortunately) just get bored and tune out. (See: Trump's efforts at making constant noise about a topic)
- Send nominee after nominee while doing this, refuse to let it leave the news cycle
Not 100% on this, but I'm somewhat positive congressional procedure here is that one can only have a single nominee at a time for a position, and since Republicans didn't actively vote it down but instead sat on it, there's not a lot he could do. He could nominate then revoke a bunch of folks, hypothetically, but that would probably just piss off the various nominees (also he'd need a list long enough to make sure that if Republicans called the bluff on one it wouldn't turn out very badly for him).
- Refuse to sign any bills until the most pressing business of filling the Supreme Court vacancy is dealt with
The only thing this would accomplish is shutting down the government right before the election (since appropriations are due Oct. 1st of each year), while claiming responsibility for it. Historically things haven't gone down well for whoever takes responsibility for a government shutdown.
- Actually charge McConnell with any of the many crimes he has surely committed in his role and remove him
Funnily enough, being convicted of a crime -- I think even being a felon? -- does not automatically remove someone from being a Senator. There's terrible precedent there, of course.
- Call upon the states for an Article V Convention to amend the Constitution to force McConnell to do his job or preferably not involve him making any decisions
This is a whole separate ball of wax that I can get into some other time, but calling an Article V convention is most likely to just end up a field day for Republicans to rewrite the constitution than it'd help Obama, for various reasons. Regardless of which party would win out it's an incredibly volatile thing to do.
- Illegally appoint a Justice anyway under the Unitary Executive Theory the GOP likes so much, because McConnell has chosen to not offer the "advice and consent" of the Senate and thus given up the Senate's ability to block the nominee.
Would be interesting to know if there's case law here for S. Ct. justices in particular, but the case law on clearly-illegal nominees (unlike the more cheeky stuff Trump has been doing) is pretty cut and dry and would probably get slapped down pretty quick.
All that said, there may have been something he could have done.