WASHINGTON – The nomination of John Bolton to be America’s ambassador to the United Nations barely made it out of the Senate Foreign Relations Committee yesterday after Senator Voinovich, a Republican from Ohio, disparaged the president’s nominee and promised to oppose him in a floor vote.

The committee approved a compromise suggested by Mr. Voinovich to send Mr. Bolton’s nomination to the full Senate without a recommendation, a rare procedure last employed in 1991, when the Senate approved Supreme Court Justice Thomas after a similarly nasty battle within the Judiciary Committee.

“I’m not so arrogant to think that I should impose my judgment and perspective of the U.S. position in the world community on the rest of my colleagues. We owe it to the president to give Mr. Bolton an up-or-down vote on the floor of the United States Senate,” Mr. Voinovich said after delivering an indictment of Mr. Bolton so stinging that the ranking Democrat on the committee, Senator Biden of Delaware, said he agreed with every word.

“It doesn’t appear that Mr. Bolton has the confidence of the majority of this committee,” Mr. Biden said. “And I would suggest that it may be worth the president’s interest to take note of that.”

Indeed, Mr. Voinovich may have provided the Democrats with talking points for the floor debate on the Bolton nomination. “I believe that John Bolton would have been fired if he’d worked for a major corporation,” the Ohio senator said. “It is my opinion that John Bolton is the poster child of what someone in the diplomatic corps should not be.”

Twisting the knife, Mr. Voinovich said that in his conversations with Secretary of State Rice, she told him that Mr. Bolton would be “closely supervised” in his new position in New York. “Why in the world would you want to send somebody up to the U.N. that has to be supervised?” he asked.

Ms. Rice yesterday, however, said she was pleased his nomination was passed out of the committee. “I recommended John for this critical position because he has the skill and dedication necessary to advance the president’s reform agenda at the United Nations,” she said. “I have believed from the outset that he is the right man for this challenging assignment, and I hope the Senate will now move quickly to confirm him so that he can begin his work at the United Nations.”

Democrats yesterday vowed to fight Mr. Bolton’s nomination when it reaches the Senate floor. Senator Boxer, a Democrat from California, pointed to a display comparing quotes of Mr. Bolton with those of witnesses interviewed by the committee that contradicted his account. Arguing that the president’s nominee perjured himself, Ms. Boxer said, “We’ll bring these quotes to the floor.”

Despite the Republican five-vote majority in the Senate, there is still a chance the Bolton nomination could be defeated. During a break in yesterday’s five-hour deliberation, Mr. Voinovich said he intended to vote against Mr. Bolton when it came to a floor vote. Senator Hagel, a Republican from Nebraska, also said as much last month when the Senate Foreign Relations Committee delayed a vote after Mr. Voinovich expressed his initial reservations about the nomination.

Yesterday, Senator Murkowski, a Republican from Alaska, appeared to have major reservations about the Bolton nomination as well. “I believe that there is a pattern of Mr. Bolton pushing that envelope … in trying to push policy that was, perhaps, more ambitious than the administration might be willing to go,” she said. At the end of her speech, she said she would vote him out of the committee.

Also on the fence is Senator Chafee, a Republican from Rhode Island. Mr. Chafee was the original Republican who expressed doubts about the nomination. Yesterday, he said he was particularly concerned about a 2003 speech Mr. Bolton gave on the eve of six-party talks with North Korea. In that speech, Mr. Bolton called North Korea’s leader, Kim Jong Il, a tyrant.

“There have been other instances where I have reservations about Mr. Bolton’s decision-making,” Mr. Chafee said before listing his diplomatic achievements and announcing that he would vote for him. Mr. Chafee is running for re-election in 2006 in a state that overwhelmingly voted against the president in 2004.

A fellow at the American Enterprise Institute who worked with Mr. Bolton, Norman Ornstein, yesterday said it was a definite possibility that Democrats could find enough Republicans to defect in a floor vote. But he also did not think that was likely if no further accusations emerged against Mr. Bolton.

“The White House is going to make this now an issue where they use a lot of political capital,” he said. “This will take something more emerging for him to go down.”

There is also a possibility that Senator Lieberman, a Democrat of Connecticut, could break ranks with his party and vote for Mr. Bolton. Last month he said he was a potential supporter of the president’s nominee. An advocacy group, Moving America Forward, has even featured some of Mr. Lieberman’s quotes in advertisements supporting Mr. Bolton. Moving America Forward briefly ran ads against Mr. Voinovich last month when he forced a delay in the committee vote.

The vote on the Senate floor is not yet scheduled. One Republican source said the vote on Mr. Bolton could be delayed until after the Senate votes on federal judges and considers a possible procedural change to do away with the filibuster on judicial nominations. Democratic sources last night said the minority party may in turn filibuster the nomination of Mr. Bolton.