Republicans worried about losing control over Congress are challenging President George W. Bush on Iraq, eroding his base of support for the unpopular war just two weeks before nationwide elections.

Increasing calls from restive Republicans for new ideas to extricate the United States from Iraq come as the White House itself seems to struggle for a better course, or at least a better way to describe the current course.

Congressional elections are Nov. 7.

Virginia Republican Sen. John Warner, chairman of the Senate Armed Services Committee, seemed to open the floodgates to Republican criticism of Iraq policy this month when he warned after a trip to Iraq that the war was "drifting sideways" and a course correction might soon be warranted.

Republicans comments in recent days:

Sen. Kay Bailey Hutchison said she would not have supported the invasion had she known there were no weapons of mass destruction in Iraq, and she has proposed splitting Iraq into three parts.

Sen. George Allen, in a difficult re-election battle with Democratic challenger James Webb, dropped his stay-the-course mantra to assert, "We cannot continue doing the same things and expect different results. We have to adapt our operations, adapt our tactics."

Sen. Conrad Burns said in a debate last week with Democratic challenger Jon Tester that he agreed with Warner's call for a change in strategy — and believed Bush already had a plan to win the war but for now was keeping it quiet. That remark drew ridicule from Democrats who likened it to Richard Nixon's "secret plan" to end the war in Vietnam.

Also challenging Bush's Iraq policy have been former Secretary of State Colin Powell, Republican Sens. Lincoln Chafee, Chuck Hagel, Susan Collins and Olympia Snowe, and several Republicans in the House of Representatives.

Click Here for More FOXNews.com You Decide 2006 Coverage

More and more, the issue is dominating election campaigns and altering the political landscape. That, and the historic pattern of midterm losses for the party holding the White House, has cast a heavy gloom over rank-and-file Republicans, particularly those on the ballot.

Democrats hope to pick up the 15 seats they need to gain control of the House, where all 435 seats are up for election, and the six they need in the Senate, where 33 of the 100 spots are up for a vote.

Republican doubts, coupled with widespread Democratic opposition to Bush's strategy, put intense pressure on the White House to do something differently, and momentum for that will build if Republicans lose the House or Senate. Bush has stopped saying he is staying the course because that suggested he was locked into a losing policy. Now Bush asserts that he is constantly switching tactics.

James A Baker III, a former secretary of state who has a long history of loyalty to the Bush family, has said the Iraq Study Group — which he leads with former Democratic Congressman Lee Hamilton — will wait until after the Nov. 7 elections to present its recommendations.

But he has suggested the panel will present Bush with options somewhere between the extremes of "stay the course" and "cut and run."

Michael O'Hanlon, a foreign policy scholar at the Brookings Institution who is part of the Baker-Hamilton study group, deemed it unlikely that Baker would lend his support to a phased withdrawal such as some Democrats have advocated. "Baker's not a political novice," O'Hanlon said.

Still, he said, the Iraq government could be told that "you've got to make some big changes" and that U.S. military backing was not forever. Might Bush announce a change in strategy before the election? "Who knows? I wouldn't rule it out," said O'Hanlon.

Click Here for More FOXNews.com You Decide 2006 Coverage

Bush could portray it to the world "as being not about the election but about the failed Baghdad security plan, and give his party a little boost before the midterms," O'Hanlon said.

Mindful of the political ramifications, the White House sought on Monday to tamp down the growing Republican criticism by portraying the president as engaged — and flexible.

He met over the weekend with his generals, and on Monday with Secretary of State Condoleezza Rice, Defense Secretary Donald H. Rumsfeld and Gen. Peter Pace, chairman of the Joint Chiefs of Staff.

White House officials said U.S. and Iraqi leaders had established "milestones" and "benchmarks" to gauge security, economic and political improvements — but that the U.S. had not issued ultimatums or withdrawal targets.

"What we aren't doing is sitting there with our heads in the ground," said White House counselor Dan Bartlett as he made the rounds of five morning television news shows. He said that the administration was "making tactical changes on a week-by-week basis as we respond to the enemy's reactions to our strategies."

Sen. Joseph Biden, the senior Democrat on the Foreign Relations Committee, told reporters that two Republicans — whom he declined to name — had told him they would demand a new policy on Iraq after the election. He said the Republican lawmakers were told not to make waves before then because it could cost the party seats.

Biden predicted many Republican defections on Iraq if Democrats win control of one or both chambers of Congress. Polls suggest there is a likelihood Democrats could take at least the House.

As to Bush's oft-repeated statement that U.S. troops will stand down as Iraqi ones stand up, Biden said, "The reason we cannot stand down is that they aren't standing together. They're killing each other."

"I don't see a big surprise with respect to Iraq that turns it around, and that's the only thing that would help the Republicans," said James Thurber, an American University political scientist. "I think it just keeps getting worse and worse, and that is not good news for the president and the incumbent party in the House and the Senate."