Democrats fight to hold onto power as election day looms

With Republicans in a strong position to capture the House, President Barack Obama on Saturday opened a four-state weekend swing to rally support for Senate candidates in Connecticut, Illinois, Ohio and Pennsylvania, hoping to build a critical firewall to protect the party's Senate majority from Republican gains across the country.

Republicans intensified their efforts to capitalise on a favourable political environment, with Sarah Palin making a last-minute trip to West Virginia to ask voters to elect a Republican to the seat that Democratic Senator Robert Byrd held for 51 years.

The outcome of five close contests will help determine if Democrats retain control of the Senate, according to the latest analysis of races, with Republicans trying to capture Democrat-held seats in Colorado, Illinois, Nevada, Pennsylvania and Washington. Though even if they sweep to victory there, they would still need to triumph in a state like California or West Virginia, where Democratic chances seemed to be improving.

The analysis suggests that Republicans are on the cusp of significantly expanding their presence in the Senate, but will need almost everything to go their way on Tuesday to gain the ten seats needed to win control.

American election: Analysis

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A sour political environment has left almost no Democratic senator on the ballot immune to forceful challenges by Republicans. Polling shows that Republicans have a firm grip on open Democratic seats in North Dakota and Indiana; senators Russ Feingold of Wisconsin and Blanche Lincoln of Arkansas have fallen behind in their races, and Harry Reid of Nevada and Patty Murray of Washington are trying to survive tough fights.

On election day, 37 Senate seats are up for election: 19 held by Democrats and 18 by Republicans. Some 14 of these seats are open - six Democratic and eight Republican - meaning there is no incumbent standing.

Also, all 435 House seats are at stake. A party must win 218 seats to get a majority. The current party breakdown in the House is 255 Democrats, 178 Republicans and two vacancies.

No contest holds a higher symbolic priority for both sides than that of Mr Reid, the Senate majority leader.He is deadlocked in a deeply personal battle with Sharron Angle, one of the most viable candidates to ascend from the Tea Party movement.

The president made an urgent appeal to save the Democratic majority, including his own former Senate seat in Illinois. He returned to Chicago on Saturday evening for a rally in the neighbourhood where his political career began, telling voters along the way that this election should not be about him.

And at an event in Philadelphia he said: "It is absolutely critical that you go out and vote. This election is not just going to set the stage for the next two years. It's going to set the stage for the next ten, the next 20."

While Republicans continued to expand the battleground in the House, growing increasingly confident in their quest to win control of at least one chamber of Congress, Senate Republicans sought to contain expectations, even though they will end the year in a much stronger position than they could have imagined two years after Obama entered the White House.

"Our hand will be strengthened, even if we're not in the majority in January," said Senator John Cornyn of Texas, chairman of the National Republican Senatorial Committee.

Millions of voters have already cast their ballots, a phenomenon that has substantially changed American elections. Democrats hoped the early-voting option in many states would help close the enthusiasm gap with Republicans, because party organisers could all but drag their voters to the polls over a span of weeks.

"It's like a dogfight in each and every one of those states," said Senator Robert Menendez of New Jersey, chairman of the Democratic Senatorial Campaign Committee.

Republicans appear to be in no danger of losing their party's open Senate seats in Kentucky, Missouri, New Hampshire and Ohio.

The difficult climate for Democrats has made simply holding on to the Senate seem like a victory even though the party stands to lose a significant chunk of its majority.

When control of the House flipped in the 1994 and 2006 elections, power in the Senate changed hands simultaneously as the Republican surge in the first case and the Democratic tide in the second carried across the Rotunda. With Republicans in a commanding position to take the House but a Senate majority still in doubt, that pattern could be broken this time.

Republicans and Democrats cite several factors for the potential disparity between the House and Senate races. One reason is that Republicans began the election cycle needing 11 seats to take the Senate majority, a number reduced to ten after Scott Brown, a Republican, won a special election in Massachusetts in January after the death of Ted Kennedy.

Republicans now have 41 senators, but Democrats would hold the edge in a 50-50 Senate because of the tie-breaking ability of vice-president Joseph Biden. Even in a favourable year, ten seats is a tall order."We were at a low point after two losses in a row," said Senator Mitch McConnell of Kentucky, the Republican leader. "We had more ground to make up."