As the House turned to a 21-day extension of a temporary law governing electronic surveillance, Republicans prepared a motion to force a vote on the long-term version passed Tuesday by the Senate.

House Republicans engineered a series of procedural votes Wednesday in a bid to derail the Democrats’ proposed extension, which President Bush said he would veto. They argued that the House should simply take up and send to the White House a surveillance overhaul bill that the Senate passed by 68-29.

Because 21 conservative Blue Dog Democrats have endorsed the Senate-passed bill, Republicans might be able to win approval of the Senate bill through a motion to recommit the extension with instructions to amend it with the text of the Senate bill.

Kevin Smith, a spokesman for Minority Leader John A. Boehner , R-Ohio, confirmed that GOP members would give it a shot. “Twenty-one Blue Dogs will be able to vote their conscience,” he said.

The shorter, stopgap measure is designed to give House and Senate conferees time to resolve their differences over the long-term legislation overhauling the Foreign Intelligence Surveillance Act. A temporary law expires Feb. 16, a day after lawmakers leave for the Presidents Day recess.

“All we’re asking for is an extension of 21 days,” said Michael Arcuri , D-N.Y. “When you think of it in the grand scheme of things, 21 days to think about whether this bill continues to give the American people the liberty they have had, that’s not much to ask.”

But Rep. Heather M. Wilson, R-N.M., said Democrats could not continue to authorize surveillance on “a month-to-month basis” without harming intelligence operations.

Earlier, Bush drew a hard line against another extension. “Congress has had over six months to discuss and deliberate. The time for debate is over. I will not accept any temporary extension,” the president said.