Washington ? Stung by revelations that his plan would cut spending less than advertised, House Speaker John Boehner on Tuesday postponed a vote on a debt-ceiling measure that was already running into opposition from tea party conservatives. The move came just a week before an Aug. 2 deadline for staving off the potential financial chaos of the nation’s first-ever default.

With time running short, the speaker promised to quickly rewrite his debt-ceiling legislation after budget officials said it would cut spending by less than $1 trillion over the coming decade instead of the promised $1.2 trillion. The vote originally scheduled for today is now set for Thursday. That may give Boehner more time to hunt for votes, but it gives Congress and the White House even less time for maneuvering.

Meanwhile, public head-butting between Democratic President Barack Obama and the Republicans showed no sign of easing. The White House declared Obama would veto the Boehner bill, even if it somehow got through the House and the Democratic-controlled Senate.

For all that, it was the tea party-backed members of Boehner’s own party who continued to vex him and heavily influence the debt and deficit negotiating terms — not to mention his chances of holding on to the speakership.

Their adamant opposition to any tax increases forced Boehner to back away from a “grand bargain” with Obama that might have made dramatic cuts in government spending. Yet when Boehner turned this week to a more modest cost-cutting plan, with no tax increases, many conservatives balked again. They said the proposal lacked the more potent tools they seek, such as a constitutional mandate for balanced budgets.

Rep. Jim Jordan of Ohio, chairman of a large group of conservative Republicans, sent a tremor through the Capitol on Tuesday when he said he doubted Boehner had enough support to pass his plan. The Boehner bill would provide an immediate debt ceiling increase but would require further action before the 2012 elections.

Obama strongly opposes that last requirement, arguing that it would reopen the delicate and crucial debt discussions to unending political pressure during next year’s campaigns.

The president supports a separate bill, pushed by Majority Leader Harry Reid in the Democratic-controlled Senate, that would raise the debt ceiling enough to tide the government over through next year — and the elections.

Boehner wasn’t helped when presidential candidate Tim Pawlenty and the groups Tea Party Patriots and Tea Party Express criticized his plan. A worse blow came when a congressional analysis said his plan would produce smaller savings than originally promised. Of particular embarrassment was a Congressional Budget office finding that Boehner’s measure would cut the deficit by just $1 billion next year.