WASHINGTON – Republican leaders in the lame-duck Senate forced a final vote on legislation to make it harder for people to erase debts in bankruptcy court. President Clinton has promised a veto if the bipartisan bill reaches his desk without changes.

Senators voted 67-31 Tuesday to end debate and continue to a final vote on the bill. They later agreed to wrap up debate on Wednesday and Thursday and set a final vote for Thursday afternoon.

In mid-1999 and early this year, the House and Senate passed differing versions of the legislation with veto-proof margins. The current compromise measure cleared the House by voice vote on Oct. 12.

For Democratic opponents of the bill, Tuesday’s vote was a bitter reversal from early last month, when so many senators were out campaigning that GOP leaders surprisingly failed to muster the 60 votes needed to move to a final vote.

It would establish a complex mathematical formula for determining whether debtors are able to repay part of their debts under a court-supervised plan rather than be allowed to have them dissolved.

Proponents of the legislation point to a rapid rise in personal bankruptcy filings in recent years, to a peak of 1.4 million in 1998, as evidence of rampant abuse of the bankruptcy court system. Opponents, including consumer groups and unions, say the legislation would hurt families hit by job losses, catastrophic medical expenses or other unforeseeable hardships that push them over the edge financially; and single mothers and their children who need alimony and support payments from bankrupt fathers.

The bill has divided Democratic lawmakers in the Senate and House. Its supporters in both parties, who have pushed such legislation for three years, have received millions of dollars in campaign money from banks and credit card companies this election year.

It wasn’t immediately clear whether the rare post-election session would run long enough to give the bill’s supporters a chance to override Clinton’s promised veto. If the measure again wins a veto-proof majority in the Senate, Clinton could choose to wait until Congress adjourns before effectively vetoing it by not signing it, thereby depriving lawmakers of the chance to override it in a new vote. By law, he has 10 days from passage of the legislation to wield his veto pen or not sign it if Congress is out of session.