Martin Longman wonders what the Senate will be like if, eventually, the filibuster on legislation is eliminated. First he notes that the Employee Free Choice Act got the support of every single Democrat in 2007, when everyone knew it was doomed anyway thanks to a Republican filibuster, but suddenly lost several votes in 2009, when a big Democratic majority and a Democratic president meant that it actually had a chance of passage:
This is the kind of dynamic that is altered by eliminating the filibuster. Hiding behind cloture votes enables you to support things your base wants but that you think are too politically perilous to support if they might actually become law. Blanche Lincoln (D-Walmart) was pro-union when it didn't count, and the Waltons were okay with that…wink, wink, nod, nod.
In the new Senate, particularly if the legislative filibuster soon succumbs, there will many fewer of these free votes, and imperiled senators in the middle will need to break with their party more often and more openly, which should provide more opportunities for bipartisan coalitions in the middle to form to cover each other's asses. Rather than joining together to block legislation, which wasn't even necessary so long as the Republicans remained united in their opposition, these senators will have to join together to mitigate the damage that could be done to their political careers if legislation actually passed. If sufficient mitigation cannot be achieved, they will have to join together to vote the legislation down.
There will certainly be fewer chances for cheap grandstanding if the filibuster is eliminated, though as Longman points out, those chances won't go away entirely. They'll stick around in circumstances when you know the House won't go along or the president has threatened a veto. In some sense, this is good: it means that parties are actually responsible for their rhetoric. If Republicans say they want to cut Social Security or ban abortion, then by God, they'll have to do it if they win control of Congress. It can't just be cheap rhetoric. Ditto for Democrats who say they want to pass labor-friendly bills or gun control legislation.
Will this mean that centrist coalitions will become more important? I'm not sure. I feel like we need to game this out a little more thoroughly to get an answer. But it might!