The top three Republicans on the Senate Foreign Relations Committee offered tepid reactions Tuesday to President Bush’s pick for ambassador to the United Nations, and two of them held out the possibility that they would vote against the confirmation of current Undersecretary of State John Bolton.

Sens. Chuck Hagel (Neb.) and Lincoln Chafee (R.I.), the second and third ranking Republicans on the panel, respectively, declined to endorse Bolton’s nomination, saying they were troubled by statements the nominee has made that appear hostile to or disrespectful of the world body.

“I do have concerns, because the United Nations is a very important institution,” Hagel said. “We need to send someone to the U.N. that has the skills to work with the secretary-general.”

Chafee said he would make “no commitments” to vote for Bolton, adding that Bush’s pick was “a surprising appointment, there’s no doubt about that.”

Even Chairman Dick Lugar (R-Ind.) appeared conflicted about Bush choosing a man regarded as a brusque U.N. foe to replace the immediate past U.N. ambassador, former Missouri Republican Sen. John Danforth, a centrist.

“I probably will vote for him, but I want to ask questions,” Lugar said of Bolton.

If just two Republicans join all Democrats on the panel in voting against Bolton, the nomination could be scuttled.

Still, all three Senators pledged to keep an open mind.

“He has a clear record on a number of these things, but I’m willing to sit down and listen to Mr. Bolton,” Hagel said.

Lugar agreed that Bolton’s performance under the scrutiny of the Foreign Relations Committee would make all the difference.

“It could be that his forward-looking views may offer either clarification or a different mindset. I don’t know,” Lugar said.

Chafee noted that “in general” he has supported the president’s nominees to all types of federal posts, but said he wanted to sit down with Bolton today and look over materials related to his nomination before making a decision.

“The rhetoric is that he’s going to support the mission of the United Nations,” Chafee said.

Democrats have already balked at the selection of Bolton, who has said that the United States should not pay its U.N. dues and made statements indicating that the body can be effective only when it is led by the United States.

Senate Foreign Relations ranking member Joseph Biden (D-Del.) said in a statement that, “In light of the President’s recent efforts to reach out to allies and the international community, I’m surprised at the choice of John Bolton to be our UN Representative. My experience with him on matters relating to Arms Control and Proliferation, and his stated attitude toward the UN gives me great pause.”

Should Bolton’s nomination survive the Foreign Relations Committee’s review, something that could come this week or next, Democrats have already indicated a willingness to oppose his nomination on the floor of the Senate.

But Bolton has shown an ability in the past to significantly moderate his positions when up for Senate confirmation to other foreign relations posts.

During a confirmation hearing in 1989, for example, Bolton seemed to express the belief that the United Nations was involved in important work.

“On a day-to-day basis, the U.N. also quietly does a great deal to improve the welfare of poverty-stricken women, children, the sick, and refugees throughout the world. These efforts deserve the fullest possible extent of support from us and other nations,” he said at the time.

But in 1994, he appeared to hold the opposite view.

“There is no such thing as the United Nations,” he said at a Global Structures conference. “There is an international community, that occasionally can be led by the only real power left in the world and that is the United States when it suits our interest and when we can get others to go along. And I think it would be a real mistake to count on the U.N. as if it is some disembodied entity out there that can function on its own.”

But in 2001 when he was nominated to his current post overseeing arms control and international security affairs, Democrats demonstrated that they could have filibustered his nomination. Forty-three Democrats voted against him, two more than is needed to sustain a filibuster. At the time, all 50 Republicans, including Lugar, Hagel and Chafee, voted for him.

Still, Lugar took pains on Tuesday to choose his words carefully as he discussed Bush’s choice of Bolton, even as he acknowledged that the nomination brings with it an unusual “controversy” for his panel.

“I am trying not to express my feelings about the nominee. … I want to hold a straight-forward hearing and give members every opportunity to address this constructively,” Lugar said.

Other Republicans on Foreign Relations appeared pleased by the nomination and defended Bolton’s past skepticism about how the United Nations is run.

“He can be very helpful and very constructive in making the U.N. operate more effectively,” said Sen. John Sununu (R-N.H.). “He’s raised concerns in the past about its effectiveness.”