WASHINGTON — Democrats yesterday said they remain opposed to President Bush’s pick for U.N. ambassador, contending that John Bolton has not yet repaired his reputation as an ineffective “bully.”

“My concern is that at the moment of the greatest need for diplomacy in our recent history, we are not particularly effective at it,” Senator Biden of Delaware, the Foreign Relations Committee’s top Democrat, said.

Mr. Biden also has said Mr. Bolton should not get a confirmation vote until the White House turns over documents he requested when Mr. Bolton was nominated last year.

Senator Dodd, a Democrat of Connecticut, cited recent press reports on Mr. Bolton’s interactions with other U.N. officials as evidence that Mr. Bolton “clearly has an aversion, in my view, to building consensus.”

A Senate Foreign Relations Committee confirmation hearing for Mr. Bolton, who has been serving as ambassador under a recess appointment, twice was interrupted by protesters opposing his confirmation.

Shrugging off the criticism of Mr. Bolton, Republicans predicted that the U.N. ambassador would be confirmed soon for the position on a permanent basis. The White House yesterday praised the work Mr. Bolton has done so far.

“We think Ambassador Bolton has done a terrific job,” the White House press secretary, Tony Snow, said. “He’s won over a lot of critics while building alliances on a range of issues, including Iran and North Korea, and working tirelessly to achieve meaningful results on reforms at the United Nations.”

Mr. Bush last year temporarily installed Mr. Bolton as U.N. ambassador while Congress was in recess, an appointment that will expire in January. The recess appointment, provided for by the Constitution, came after Democrats blocked repeated attempts by GOP leaders to grant Mr. Bolton Senate approval.

“The sole thing that remains is the constitutional authority of the Senate to give its advice and consent,” Senator Warner, a Republican of Virginia, said.

“I do believe without any reservation whatsoever that the Senate will and should give that advice and consent to this nominee because he becomes an integral member of the president’s national security team at a time when our nation is faced with these many complex issues,” Mr. Warner added.

Speaking from prepared testimony, Mr. Bolton called for a “durable solution” to the violence in the Middle East and the need to “defang” Hezbollah.

“We are actively considering a variety of methods” to disarm Hezbollah, including establishing an international security force in the region, he said.

Mr. Bolton also said America remains committed to bringing peace to Darfur.

Mr. Bolton said some “modest progress” has been made in U.N. reform. “The goal now is to identify priority targets where progress can be made” and create a “lasting revolution of reform,” he said.

By resubmitting Mr. Bolton’s nomination to the Senate, the president has made clear “that Ambassador Bolton is important to the implementation of U.S. policies at the United Nations and to broader U.S. goals on the global stage,” said Senator Lugar, a Republican of Indiana, chairman of the Senate Foreign Relations Committee.

Mr. Bolton has the green light from Senator Voinovich, a Republican of Ohio, who last year sided with Democrats in opposing the president’s nomination. While Democrats are still expected to oppose the confirmation, Mr. Bolton also has retained the support of other key GOP senators.