The going seems to be getting tough for Arlen Specter.

After Announcing In January ...
... that he would not challenge U.S. Sen. Arlen Specter, R-Pa., in the 2010 Valley congressman Pat Toomey may have had a change of heart.

In an interview on WAEB-AM in Allentown, the Club for Growth boss told host Bobby Gunther Walsh that a Senate bid is "now back on the table." Toomey made headlines when he said he was forgoing a repeat of his 2004 challenge to focus on a run for governor.

But with conservatives now baying for Snarlen's blood over his support for The Stim and state GOP Chair Rob Gleason saying the party may not endorse Specter for re-election, there's apparently blood in the water.

In 2004, Specter had the benefit of both the Bush administration and his junior Senator, the arch-conservative Rick Santorum, to help him limp across the finish line in a contested GOP primary against Pat Toomey. With Bush out of the White House and Santorum out of the Senate, Specter's chances against Toomey this time around, should the far right activist indeed decide to jump in the race, could be significantly more difficult.

It's still not clear whether this is real, or instead just a threat; Toomey may actually be interested in running, or he may just be interested in making Specter think he is running to force the senior Senator to vote more conservatively (remember, he was one of just three Republicans to vote for Barack Obama's stimulus plan).

My guess is that Specter will start looking over his right shoulder, making him a less available target for the Obama White House's bipartisan outreach. But while in the short run that mean that it might make it more difficult for progressive legislation to make it through the Senate, the long term outlook is significantly better. If Specter wins the primary this time, he won't be beholden to the right in the same way he was six years ago. If Toomey pulls out a victory in the primary, he would have much less of a shot than Specter of winning in the general as his views put him way out even beyond Santorum, who earned just 41 percent in his reelection bid three years ago.