With the threat of sectarian violence spinning into all-out civil war and American casualties exceeding 2,500, the war in Iraq has emerged as a dominant issue in many of the 2006 congressional campaigns.

"Iraq is a bigger issue in 2006 than 2004. 2004 was bigger on the war on terror. Now the discussion is on Iraq," said Kellyanne Conway, president and CEO of the Republican polling firm the Polling Company.

And public opinion polls indicate growing opposition to the president's handling of the issue. Over 62 percent of Americans are unhappy with the way that the Bush administration has handled the war in Iraq, according to a July 2006 Gallup Poll. As long as a year ago, six out of 10 Americans were saying the war was not worth fighting, according to a Washington Post-ABC poll.

Democrats have sought to capitalize on the flagging support by hammering on Republican candidates from Connecticut and Virginia to Ohio and California. But as a party, the Democrats have been unable to settle on one position on Iraq. Some, led by former presidential nominee Sen. John Kerry, D-Mass., have called for an immediate timetable and withdrawal of U.S. forces, while others have urged plans for leaving but on no announced schedule.

GOP strategists, including White House adviser Karl Rove, have countered that the paths the Democratic Party advocates would cede Iraq to the Islamic extremists and leave the geopolitically critical nation embroiled in civil war.

The two parties' positions leave voters in a quandary, analysts say.

"[I]f the voters are confronted with two parties, one party is the Republicans who screwed up Iraq, and the other party is the Democrats who seem to want to cut and run, or seem to be defeatist, or who don't have a policy toward Iraq, well, then what are they going to choose?" said New York Times columnist David Brooks in late June. "That's actually a tough decision."

Although the Democrats have had trouble outlining a single policy on Iraq, the party is fielding a series of candidates that have outlined clear policy differences as they challenge incumbents who supported the war.

In Pennsylvania, Patrick Murphy, former U.S. Army Captain in Iraq, is challenging incumbent Republican Andy Warren. Murphy was a former Republican who switched to the Democrat Party while he was a soldier in Iraq. He says that he was angered when more troops were needed, and the Pentagon tried to cut soldiers' pay. Murphy has proposed a three-stage troop withdrawal with 100,000 troops deployed by the summer of 2007.

Tammy Duckworth, an Iraq veteran who lost both legs when the helicopter she was piloting was attacked, is contending for a seat in one of Illinois' closely watched contests.

James Webb, the Democratic retired Vietnam veteran is challenging U.S. Sen. George Allen, R-Va., running largely against Allen's support for the war. He claims that he "knows how to bring the war to an early and honorable end."

But Iraq is not strictly a Democrat-vs.-Republican issue. In Connecticut, Democratic Sen. Joseph Lieberman, the most pro-war of Democrats in the Senate, lost his party nomination in August to millionaire Ned Lamont largely because of his support for the war.

"What's significant about this election is that what is obvious is that the status quo, the stay-the-course Bush policy of the status quo in Iraq, is politically unacceptable to a vast majority of Democrats, to a majority of independents, and to a sizable minority of Republicans," said syndicated columnist Mark Shields on the NewsHour.

During his primary campaign Lieberman stood by his commitment to the war, saying the United States must continue its presence in Iraq. With the backing of liberal activists and party members, Lamont put the war and Lieberman's closeness to President Bush at the center of his campaign.

"The people of Connecticut voted for change," Lamont said on the NewsHour the day after his primary win. "They don't want to stay the course in Iraq; they don't want to stay the course here in America. ... I think Iraq is a defining issue. Are we safer than we were before the invasion of Iraq? Have we destabilized the Middle East? Have he emboldened Iran? Is Israel any safer? I think the answers to those questions are kind of clear, that the war in Iraq was a bad decision for this country."

Lieberman filed to run as an independent candidate in the November general election, saying he will offer a choice to voters in the middle of the political spectrum.

President Bush, meanwhile, has remained committed to maintaining American forces in Iraq until the new government has the ability to secure itself.

"[Iraqi] Prime Minister [Nouri] Maliki was very clear this morning; he said he does not want American troops to leave his country until his government can protect the Iraqi people. And I assured him that America will not abandon the Iraqi people," he said July 25.

For Republicans on the stump, the question is how closely to align their positions with that of their president, and for Democrats looking to take control of Congress, the challenge remains to offer another way forward in Iraq.

-- Compiled by Kathryn Cohen for the Online NewsHour