On the Home Front, the Battle Over Haiti Rages : Congress: Clinton faces bitter, bipartisan opposition from lawmakers. But the invasion appears inevitable.

Opposition to a U.S. invasion of Haiti mounted steadily in Congress on Wednesday as the Senate opened debate on the U.S. military buildup aimed at forcing out the Haitian junta.

Senior Democrats warned that if President Clinton heeds mounting GOP calls to seek congressional approval before using force, he is likely to lose in the House and Senate because of widespread opposition to his policies, even within his own party.

Scrambling to protect the President from an embarrassing foreign policy defeat during the final preparations for an invasion that now appears inevitable, Democratic leaders resorted to a series of procedural maneuvers to block Republicans from forcing a vote on a non-binding resolution opposing military intervention.

Although it was not in session, a similar crisis loomed in the House, where Democratic leaders were looking for ways to defuse a bipartisan effort to deny funds for the invasion of Haiti without congressional approval.

The fight in the House is expected to come to a head early next week, but distrust of the Administration appears to be running so high that some Democrats said privately they suspected that the timetable for an invasion is being driven in part by Clinton’s concern about the growing congressional opposition.

Senate Republicans had been clamoring for a vote on the resolution before Clinton addresses the nation on the Haitian crisis tonight.

But when Senate Majority Leader George J. Mitchell (D-Me.) succeeded in postponing the showdown until next week, Sen. John McCain (R-Ariz.) angrily charged that Mitchell’s timing was suspect because most lawmakers now assume the invasion will be launched before then.

“The Democrats . . . are doing everything they can to block a vote because they know they would lose it,” McCain said, adding that it is “unconscionable” that the Senate is being prevented from considering even a symbolic resolution on a matter involving “war and peace.”

A vote now in the House and Senate would raise “formidable problems” for Clinton because he would “in all likelihood lose it,” warned Rep. Lee H. Hamilton (D-Ind.), chairman of the House Foreign Affairs Committee.

“Then you’d have a situation with the President charging off in one direction and the Congress in another, and what kind of signal would that send about American foreign policy around the world?” Hamilton asked at a breakfast meeting with reporters.

But even as they maneuvered to spare him from legislative rebuke, Democratic leaders also urged Clinton in public and in private to hold off on an invasion and take more time to consult with Congress.

There should be “no rush to invade Haiti. We’re not threatened,” House Deputy Whip Bill Richardson (D-N.M.) said. “It would behoove him to wait and to explain to the American people and the Congress why he wants to take this action.”

That caution was echoed in the Senate debate by Sen. Sam Nunn (D-Ga.), the influential chairman of the Senate Foreign Relations Committee, who said that Clinton needs to explain “more clearly what our stake is, what our interests are and what our goals are” before launching an invasion.

Nunn said that, while an invasion would be “quick, decisive and overwhelming,” the Administration’s goal of restoring democracy would “clearly be a long and expensive process . . . costing hundreds of millions of dollars” and requiring a long-term U.S. presence, which the American people have not yet been prepared to accept.

Hamilton said he has come to the “very reluctant” conclusion that intervention in Haiti is necessary because the crisis has reached the point where the “credibility, reliability and prestige of American foreign policy” are at stake.

But Republicans, arguing that Clinton brought the crisis upon himself by mishandling Haiti, charged that it is only Clinton’s credibility that is at stake.

“If they have a credibility problem, it is self-inflicted . . . and that’s not worth risking American lives for,” Senate Minority Leader Bob Dole (R-Kan.) said.

In its belated efforts to consult with congressional leaders over the last few days, the Administration has cited the Grenada and Panama interventions as models for the current crisis.

But the model most jittery lawmakers have in mind is Somalia, from which U.S. peacekeepers were finally withdrawn after suffering heavy casualties in a firefight with Somali guerrillas, a senior Democratic foreign policy aide noted.