Tom Harkin is threatening to actually force the Republicans to filibuster. Yglesias says its too hard:
I’ll believe this when I see it. Breaking a filibuster via attrition is more difficult than is generally realized. The minority needs to have at least one guy available at all times to hold the floor and keep talking. The majority, meanwhile, needs to have basically all its guys on hand at all times. Otherwise, the minority can “note the absence of a quorum” and everything stops until everyone can be dragged into the chamber. It’s a bigger pain, in other words, for the majority than for the minority which is why you generally don’t see it attempted.
Of course it's a bigger pain. Who cares! This is why you are a Senator!!! Is it going to suck to sit there at 2 am to listen to Tom Coburn blather on? Of course it is. But it's also going to focus the nation's attention on Republican obstructionism. Choose a popular bill and go for it. Something to do with veterans' affairs would be a great choice. I guess the Democrats would rather spend time fundraising than actually getting legislation passed. Bring some cots into the chamber and sleep there for Christ's sake.
Moreover, is there any questions Republicans would go to the mat to stop Democratic filibusters? Why are Democrats always weaker?