Updated

Senate Democrats are sounding out former State Department officials and at least one current one as they try building a case against the confirmation of John R. Bolton (search) as U.N. ambassador, congressional aides said Thursday. The State Department rallied behind him.

Department spokesman Richard Boucher said Bolton would defend himself against the criticism and said documents had been sent to the Senate Foreign Relations Committee (search) to counter the accusations. The committee plans three days of hearings beginning Monday, with panel Chairman Richard Lugar, R-Ind., hoping for a vote next Thursday.

"We don't see any grounds for questioning his nomination or confirmation," Boucher said.

So far, the only likely witness besides Bolton is Carl W. Ford Jr., a former chief of the department's bureau of intelligence and research. Ford clashed with Bolton while at the State Department over what Ford regarded as Bolton's intimidation of department intelligence officials, The New York Times reported Thursday.

Norm Kurz, a spokesman for Sen. Joseph Biden, D-Del., said the State Department had agreed to let Democrats interview four State Department officials.

According to committee aides who spoke on condition of anonymity, among critics being contacted by committee Democrats is Christian P. Westermann, a department intelligence officer who, according to the Times, also has clashed with Bolton. A senior State Department official said they would make Westermann available to Democrats.

But Kurz said he believed Democrats had not yet received documents they have requested.

Among them were papers relating to a speech Bolton made in 2002 in which he said Cuba was trying to develop biological weapons and was transferring its technical expertise to countries hostile to the United States. At the time, some officials said the information should not have been publicly disclosed. Cuba has denied the weapons allegation.

Bolton will testify Monday. Andy Fisher, the commitee spokesman, said Ford was likely to testify Tuesday.

President Bush's nomination of Bolton, the undersecretary of state for arms control and international security, has stirred controversy because of his blunt style, opposition to a number of treaties and outspoken criticism of the United Nations.

Five of the six living former Republican secretaries of state — all but Colin Powell — have signed a letter to Lugar praising Bolton. Powell had no comment, a spokesman said.

Powell, who headed the State Department in Bush's first administration, was known to have serious policy differences with Bolton. As Powell tried to lure North Korea into nuclear disarmament negotiations Bolton publicly denounced North Korea, with severe criticism directed at leader Kim Jong Il (search).

Democrats are hoping to persuade moderate Sen. Lincoln Chafee, R-R.I., to oppose Bolton, which could delay or even scuttle the nomination. Republicans control the panel by 10-8, and Chafee spokesman Stephen Hourahan has said the senator is inclined to support Bolton but is undecided. The committee would need a majority vote to recommend confirmation by the full Senate.