Maine Sen. Angus King to hold press conference at 3:30 ET to discuss which party he'll caucus with; Update: Not switching

Looks like Dan Sullivan from Alaska is going to end up being Republican senator number 53, with Bill Cassidy hopefully to follow as number 54 next month in Louisiana.

Is Angus King number 55?

He was telling everyone who’d listen last night that he’s open to caucusing with the GOP if they retook the Senate. That appears to be his Plan B. Plan A was (or is?) to organize some sort of independent/centrist caucus in the Senate that would serve as a balance of power between the two parties. Er, why would any Republican moderate want to join a caucus like that now that they’re back in charge, knowing that it might cost them committee chairmanships to do so?

It’s one thing to switch parties, as Joe Manchin might conceivably do. That would indicate a commitment to one’s new caucus that would, presumably, persist even if the other party takes the Senate back in 2016. There’s value in that. What would the GOP get, though, from accepting King into the fold and handing him some plum committee slots, with no assurance that he wouldn’t turn around and caucus with Democrats again two years from now? It’d be one thing if they were sitting at 59 votes and he was promising to be the 60th vote for cloture on all bills supported by the leadership, but even with 55 seats Republicans would be nowhere near that. In which case, why would they care if King wants to caucus with them? What’s he offering here? Stay tuned. He’s going to speak at 3:30.

Update: If Sullivan and Cassidy win and King and Manchin both agree to caucus with the GOP, now you’re at 56 seats. The closer you get to 60, the more attractive it is to add indies and centrist Democrats to your caucus. But, er, there are no indies and centrist Democrats left after these two, right? All the red-state Democrats lost last night!

Update: Would this make it worthwhile for the GOP?

King’s vote won’t matter to cloture but it might matter to passing bills out of committee if there are defections among the Republican members.

Update (Ed): It matters for positioning in 2016. The GOP can argue that they are the true party of broad-based governance if they can attract an independent like King to switch caucuses, and a Democrat like Manchin to switch parties. It would be a PR move, and a wise one at a low cost. They might bargain more for Manchin than for King, who really has nowhere else to go as an independent, but both Senators would still be joining the GOP caucus on the GOP’s terms.

And they may not be alone, either, as Allahpundit noted on Twitter. McConnell says three “prominent Democrats” may be thinking about a switch, or at least friendlier terms:

Update (AP): Clown show, bro.