After the 2004 election, Tom DeLay crowed that Republicans were at the dawn of a "permanent majority". A year later, things are not looking so hot for Republicans.
Bush has been hovering in the 38-41 range. The Republican Congress is in the 30s. Democrats have opened up big leads in the generic congressional ballot. Republicans are reeling from investigations and indictments of all their top players. Republicans are going down hard in several key states, including Ohio and Missouri. And people are incrasingly dissatisfied with the direction of the country.
So really, given the tenuous hold on power of the Republican Party, do Republicans really want to ditch the filibuster? Because it won't be long before Democrats retake the White House and congress. And it sure will be nice to need just 51 votes to pass legislation and confirm nice, solid, liberal judges.
I say test the GOP. If we don't use the filibuster out of fear they'll pull the nuclear option, then there is no practical filibuster in existence anyway. Force them to pull the trigger. Let's see just how confident they are in their "permanent majority" status.
Because the way things are going for Republicans, it won't be long before Democrats reap the benefits.