All eyes in the Senate were on Republican Judd Gregg of New Hampshire Thursday amid speculation that President Obama is seriously considering him as his Commerce secretary.

For his part, Gregg refused to comment on reports that he is a finalist. Obama had earlier tapped Democratic New Mexico Gov. Bill Richardson for the position, but he withdrew in December amid a federal corruption probe.

“I really don’t have any comment on that at all,” Gregg said. Later he added, “I can’t comment at all on this.”

If Obama were to nominate Gregg, it could have significant implications for the Senate. Under New Hampshire law, Democratic Gov. John Lynch would appoint a replacement who would serve until Gregg’s term expires in 2010. If Democrats also win an undecided Senate race in Minnesota, that would give them 60 seats, enough to choke off debate with a unified caucus. Republicans bristled at that possibility and suggested Gregg might face pressure to turn down the job if offered.

Senate Majority Leader Harry Reid , D-Nev., offered little more than Gregg did.

“That’s what I’ve heard, but I don’t know,” Reid said when asked whether Gregg, the Budget Committee’s ranking Republican, is under serious consideration.

Asked to confirm that the Obama administration had contacted him to gauge his support for Gregg moving to Commerce, Reid responded, “I’m not getting into any of my contacts with the White House.”

The White House was also tight-lipped but stopped short of ruling him out. Obama spokesman Nick Shapiro said, “We’re not going to play the name game, but the president hasn’t made a pick.”

Sen. John D. Rockefeller IV , the West Virginia Democrat who leads the Commerce, Science and Transportation Committee, said he had heard the possibility that Gregg’s name was being floated for Commerce secretary. “It was mentioned on the floor a couple of times, just informally,” Rockefeller said. “That name is now floating — as you know — and I know very well that we don’t have a Commerce secretary.”

Reid signaled support for Gregg, saying “He’s one of my best friends in the Senate,” said the majority leader. “He’d be competent doing whatever he wants to do.”

Budget Committee Chairman Kent Conrad , D-N.D., said it would be a “considerable loss to the committee and to the Senate if he were to leave.” Conrad added that Gregg could excel at the Commerce post because “he is hard-working, he’s got excellent judgment and he’s got a very good understanding of the economic condition of the country.”

Minority Whip Jon Kyl , R-Ariz., said he had not heard of Gregg being considered for Commerce but joked that it would be “a pretty sneaky, sneaky move to get a really good person as Commerce secretary and put us in a bind politically.”

Kyl said Gregg likely would face pressure from other GOP senators to turn the job down if he were offered it.