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There was a bit of an awkward moment at a Republican news conference on Capitol Hill today, highlighting Republican presidential candidate Rick Santorum's lack of support among his former colleagues in the Senate.

No sitting senator has endorsed the Pennsylvanian, even though he served in the chamber for 12 years (until 2007) and worked his way into the party's leadership as chairman of the Senate Republican Conference.

By comparison, for Massachusetts Gov. Mitt Romney has been endorsed by 14 senators.

When asked about Santorum during an unrelated news conference on jobs today, his former colleagues took pains to avoid comment, awkwardly looking at each other, with no one volunteering to respond to the question at first.

"He's certainly a very nice person," Sen. Kay Bailey Hutchison, R-Texas, said, declining to step forward to the podium and microphone to comment. "I am not going to do presidential politics right now."

Sen. John Thune, R-S.D.,  took the chance to speak about his endorsement of Romney instead. "I came out early for Governor Romney and my reasons for that were very clear. I believe with jobs and the economy the paramount issue that he's got the best skill set, best experience to help tackle those issues," Thune said. "He's in the best position to win the general election."

And while Santorum, 53, certainly isn't holding his breath for an endorsement from Sen. Pat Toomey, R-Pa., the senator signaled he would not be endorsing anyone right now.

(Santorum endorsed then-Pennsylvania Sen. Arlen Specter in 2004 over then-Rep. Pat Toomey for the Republican Senate primary.)

"I have not weighed in on the presidential primary," Toomey said. "I think we have had a number of strong candidates and we still do and I will watch with great interest as the voters sort this out."

The news conference was then cut off by an aide to one of the senators.