WASHINGTON (AP) — House Speaker John Boehner hastily reworked his stalled emergency debt-limit bill Friday as Senate Democratic leader Harry Reid signaled he’s pushing ahead with his own version. President Barack Obama declared “we’re almost out of time” in a wrenching political standoff that has heightened fears of a market-rattling government default.

“The power to solve this is in our hands on a day when we’ve been reminded how fragile the economy already is,” the president said from the White House as U.S. fell in response to a sour report on economic growth and widespread uncertainty over the Washington debt stalemate. “This is one burden we can lift ourselves. We can end it with a simple vote.”

A simple vote was hard to come by, just a few days before Tuesday’s debt-limit deadline.

On Capitol Hill, Reid pressed forward with his legislation, setting up a showdown vote for Sunday. And Boehner moved to revise his measure in hopes of winning over reluctant rank-and-file conservatives who argue that the deficit cuts it contains are insufficient. House Republican leaders met behind closed doors with their members in a last-ditch appeal after abruptly postponing a vote that had been expected on Thursday.

Rep. David Dreier of California said the revised measure would still raise the nation’s debt limit by $900 billion — essential to allow the government to keep paying its bills — and cut spending by $917 billion. But a later increase in borrowing authority wouldn’t take effect unless Congress sent a constitutional balanced budget amendment to the states for ratification.

That was a key demand of rebellious conservatives who withheld their votes from the legislation on Thursday night.