The battle to control Congress was down to a sprint Monday, with President Bush and House Minority Leader Nancy Pelosi dueling down the stretch to sway undecided voters, and convince others that with just 36 hours remaining every vote counts.

Republicans and Democrats sent thousands of volunteers to states with the most contested races to work phone banks and canvass neighborhoods as candidates in the midterm elections neared the finish line.

The greatest obstacle for both parties is the historical tendency for voter turnout to be mediocre — or even poor — in off-year elections. For those who do vote, both parties have put together legal teams for possible challenges.

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Up for grabs are 435 House seats, 33 Senate seats, governorships in 36 states, and thousands of state legislative and local races. In 37 states, voters also will determine the fate of ballot initiatives, including whether to ban gay marriage, raise the minimum wage, endorse expanded embryonic stem cell research and — in South Dakota — impose the country's most stringent abortion restrictions.

President Bush was spending Monday urging Republicans in Southern states to get out and vote.

"Here's the way I see it," the president told a crowd Sunday in Grand Island, Neb. "If the Democrats are so good about being the party of the opposition, let's just keep them in the opposition." Republicans are hoping their party's acclaimed get-out-the-vote operation can prevent a Democratic rout in a campaign marked by voter fury over the Iraq war.

Republicans repeated their assertion that Democrats would raise taxes and prematurely pull out of Iraq if they controlled Congress. Democrats pressed their case for change, arguing that Republicans on Capitol Hill blindly have followed Bush's "failed policy."

Rep. Nancy Pelosi, D-Calif., hoping to become the first female House speaker, stumped for Democratic challengers in the Northeast.

She was cautiously optimistic Sunday about her party's chances in Tuesday's midterm election. "We are thankful for where we are today, to be poised for success," she said in Colchester, Conn. "But we have two Mount Everests we have to climb — they are called Monday and Tuesday."

Her party appears increasingly confident it can ride a wave of public disenchantment with the Bush administration and Congress to victory in the House and, possibly, the Senate.

Iraq has dominated the campaign season, and Republicans and Democrats sparred over the war again Sunday following Saddam Hussein's conviction on crimes against humanity. He was sentenced to die by hanging; an appeal is planned.

"To pull out, to withdraw from this war is losing. The Democrats appear to be content with losing," said Sen. Elizabeth Dole of North Carolina, who leads the Senate GOP's campaign efforts.

Rep. Rahm Emanuel of Illinois, the Democrat in charge of the party's House campaign, shot back, "We want to win and we want a new direction to Iraq."

The number of ballots cast historically is low in nonpresidential year elections, with only about 40 percent of U.S. citizens of voting age population going to the polls.

The Associated Press contributed to this report

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