I've seen a lot of comments and diaries warning that we should be careful about kicking Lieberman out of the caucus. I not only think this shouldn't be a concern, but I think that we are much better off with Lieberman as a Republican, and not just for ideological reasons. Tactically, we need Lieberman in the Republican party.
I realize this seems a little counter-intuitive. But stay with me...
* To start with, remember that Lieberman's only importance is now on cloture votes.
We do not need Lieberman to vote for majority leader, to fill committee positions, or even to get basic majority votes on most legislation. Our substantial majority means that Lieberman won't be needed to get most legislation out of committee.
The only real place it will be a problem is when there's a cloture vote. So, bearing that in mind, also consider...
* Ultimately, Lieberman is, at heart, a Broderista. He lives to capitulate.
Lieberman has proven, ever since his infamous scolding of Clinton from the Senate floor, that the moments he lives for are to appear at the press conference with a bipartisan group of Very Serious People and say, in earnest tones, that now is not the time for partisanship. If he stops doing this, he has no purpose in life.
* There is nothing mavericky, centristy, or Broderish about voting along party lines in a cloture vote.
Remember the first point. The only time Lieberman matters is during cloture votes. And given remember what a cloture vote is -- it determines the success or failure of a filibuster, which only matters at times when legislation is coming down to the wire and partisan tensions are high. Always remember that these are the moments when Lieberman gets the overwhelming desire to get up on the podium and be considered a Very Serious Person.
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Now, remembering the above points. Imagine this scenario -- Obama's health care plan clears the House, and heads to the Senate, where the Republicans manage a last stand by rousing together a filibuster. For the sake of argument, let's imagine the Senate numbers end up in the scenario where Lieberman theoretically matters most -- Democrats have 58 seats plus Bernie Sanders.
If Lieberman caucuses with the Democrats...
A vote against cloture would just be seen as riding the pine with his party. (The media will invariably interpret Lieberman to be a member of whichever party he caucuses with.) There will be a real risk that Lieberman will decide he needs to "go rogue," and vote against cloture, for whatever dumbass reason he comes up with.
On the other hand, if Lieberman caucuses with the Republicans...
The tension is running high -- will Lieberman vote for cloture? No! He comes out and announces (at a Very Serious Press Conference, of course) that he cannot vote for the legislation, but that in the interest of bipartisanship or mavericness or whatever excuse he provides, he must support an "upperdown vote." And David Broder nods sagely in approval.
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Fundamentally, it comes down to this: When you have a guy who gets the overwhelming urge to capitulate at moments of greatest import, do you want him on your team or the other team?
If it were still a closely divided Senate, I'd say let's keep him, as we'd need him for close roll call votes. But if all we need him for is cloture, we're not only just as good, but we're better off with him on the GOP side of the aisle.