WASHINGTON — House Speaker John Boehner abruptly canceled a vote on his plan to lift the federal debt limit late Thursday after failing to persuade recalcitrant conservatives to back the measure and help him avert an economy-rattling default.

After a night of legislative chaos and with control of his caucus slipping from his grasp, Boehner, R-Ohio, yanked the bill from the House floor and prepared to make changes aimed at appealing to his tea-party-influenced right flank. Republican aides said they hoped for a Friday vote.

But with GOP leaders unable to offer assurances that the needed support would materialize, Senate Democrats planned to proceed with their own debt-ceiling plan in hopes of pushing a measure through Congress by Tuesday, when the U.S. Treasury says it could begin running short of cash to pay the nation's bills.

The late-night drama developed after debate on Boehner's debt-limit bill had concluded and lawmakers were minutes away from what was expected to be a cliffhanger vote. Suddenly, action on the House floor shifted to a series of noncontroversial measures, befuddling lawmakers.

Outside the House chamber, Boehner summoned members of the holdout GOP South Carolina delegation to his office just off the Capitol Rotunda. But within minutes, freshman Reps. Mick Mulvaney and Jeff Duncan left the meeting, saying they were heading to a chapel to pray for their leaders.

Rep. Tim Scott, R-S.C., later joined them, and the three said Boehner's pitch had not been persuasive.

"Divine inspiration already happened," said Scott, a liaison to party leadership for the Republican freshman class in the House. "I'm a no."

Soon after, the South Carolinians gathered with other undecided Republicans in the offices of House Majority Whip Kevin McCarthy, R-Calif. There, Boehner, McCarthy and House Majority Leader Eric Cantor of Virginia pleaded with fellow Republicans for support.

Aides said some holdouts objected to an item in the bill related to the Pell Grant college-loan program, complaining that it amounted to a $17 billion spending increase. Some members also wanted to see stronger language calling for a constitutional amendment to require a balanced federal budget, aides said.

Failure to pass the measure would represent a significant defeat for Boehner, the first-year speaker who has invested much political capital in trying to sway his fractious majority.

Although they knew the vote was going to be close given the philosophical objections of many House Republicans to an increase in federal borrowing power, Republicans earlier Thursday had made it clear that they expected to pass the legislation in an effort to force the Democrat-led Senate into accepting it.

Across the Capitol, Senate Democrats had been waiting to put the Boehner bill to a quick death in a late-night vote of their own. But with House Republicans in another closed-door meeting, Senate Majority Leader Harry Reid, D-Nev., said on the Senate floor that Boehner and his allies appeared to be "having trouble passing their bill."

The chaos in the House left the government no closer to a resolution over the debt limit just days before the Aug. 2 deadline. The national debt hit the current $14.3 trillion limit in mid-May. Unless Congress acts, the government will be in danger of defaulting on its obligations as early as Tuesday.

The partisan impasse is shaking Wall Street and the confidence of top business leaders. Early Thursday, chief executives of some of the largest U.S. financial companies — including Brian Moynihan from Bank of America, Jamie Dimon from J.P. Morgan Chase and John Strangfeld of Prudential — wrote a letter to President Obama and members of Congress urging them to strike a deal this week.

"The consequences of inaction — for our economy, the already struggling job market, the financial circumstances of American businesses and families, and for America's global economic leadership — would be very grave," they wrote.

Wall Street, meanwhile, suffered fresh losses as the Dow Jones industrial average was down for a fifth straight session.

Administration officials have warned of potentially calamitous effects on the economy if the country defaults on its obligations: a spike in interest rates, a plunge in stock markets and a tightening in the job market in a nation already struggling with unemployment higher than 9 percent.

If the House proves unable to pass a bill, action is likely to shift to the Senate, where Reid was preparing to proceed with his own debt-limit measure, perhaps as soon as Friday evening.

Material from The Associated Press and The New York Times is included in this report.