Massachusetts Gov. William Weld’s long-shot campaign to become ambassador to Mexico got a boost Friday when the No. 2 Republican on the Senate Foreign Relations Committee acted to force a hearing over Sen. Jesse Helms’ objections that the nominee is soft on drugs.

But even as Indiana Sen. Dick Lugar made his move, Senate Majority Leader Trent Lott said President Clinton’s nomination appears to be dead because of Weld’s maneuvers, which have heightened a GOP rift between conservatives and moderates.

In requesting a special meeting to consider moderate Republican Weld for the ambassador’s post, Lugar said committee members and the Senate have the right to question the nominee’s positions in open debate.

“Denying a hearing to a presidential nominee is not the way to make these points in a democratic society,” Lugar said in a letter to his committee colleagues. “Such a silencing tactic could be expected in a country that is not free. But the United States has always been the champion of political freedoms, open debate and an individual’s right to answer critics.”

Helms last year used seniority to supplant Lugar, a foreign affairs expert, as Foreign Relations chairman, At the White House, spokesman Joe Lockhart said, “We think the best thing for the governor to do is to go out, meet with senators and talk publicly about why he’ll be an excellent ambassador to Mexico and why it’s important for the Senate to give him his day and give him a fair hearing.

“Defending the argument of no hearing is very difficult. It becomes even more difficult faced with a public discussion,” Lockhart said.

Staunchly conservative Helms, R-N.C., has refused to schedule a hearing for Weld, whom he maintains isn’t the right man for the job in drug-plagued Mexico.

Helms considers Weld soft on drugs for supporting the medical use of marijuana and a needle-exchange program to slow the spread of AIDS. On another divisive issue in GOP ranks, Weld supports a woman’s right to an abortion - which Helms wants outlawed.

Helms has three working days to consider Lugar’s request, which also was signed by Sens. Gordon Smith, R-Ore., John Kerry, D-Mass., and Joseph Biden, D-Del.

If Helms refuses to yield, Lugar said he would circulate a petition next week to set a hearing time and place. With the support of Smith and the eight Democrats on the panel - expected, but not guaranteed - Lugar would prevail. Nonetheless, the chairman retains the power to set the topic at any hearing, and he could choose to ignore Weld.

“Senator Helms will not put William Weld’s nomination on the agenda,” said Marc Thiessen, a Helms spokesman. “Weld accuses Helms of ideological extortion. Well, Weld is saying, ‘Jesse, either you approve my nomination or I will start a war within the Republican Party.’ That’s hypocrisy. … If he thinks that’s going to get him to Mexico, he’s sadly mistaken.”

Lott, in an interview on CNN’s “Evans & Novak” program scheduled to air today and Sunday, agreed with that view, saying, “Weld has conducted himself, certainly not very diplomatically.

“The way he has handled himself when he’s been in Washington, it has not been helpful. And it appears to me the nomination is dead,” Lott said.

Most of the 10 committee Republicans support Helms, including four who urged Clinton to withdraw Weld’s name: Sens. Paul Coverdell of Georgia, Craig Thomas of Wyoming, Chuck Hagel of Nebraska and Rod Grams of Minnesota.

In a letter to Clinton released Friday, the senators also criticized the Democratic president, saying, “There is no room for the political considerations which were clearly the priority with former Governor Weld’s nomination.”

But Gov. Terry Branstad of Iowa, chairman of the Republican Governors’ Association, said: “I don’t think one committee chairman ought to be able to block or prevent somebody from being confirmed.”

Weld, who has portrayed his bid as a fight for the soul of the Republican Party, continued his rounds on Capitol Hill Friday, meeting with Grams.