The presidential primaries have diverted attention from down-the-ballot House and Senate races, yet political observers say Congress could be where the Democrats win their most significant victories in November.

While polls show Sen. John McCain and Sen. Barack Obama running neck and neck for the presidency, the Democrats appear poised to significantly expand their congressional majorities. A couple of factors are tilting key races their way.

First, the faltering economy, gas prices, and the ongoing war in Afghanistan and Iraq seem to be higher priorities for voters than social issues. Second, in regions where social issues still count with voters, Democrats are once again nominating faith-friendly social moderates in some conservative congressional districts, a strategy they employed with some success in 2006.

So long as the strategy works, Democratic leadership will continue to recruit candidates from the conservative wing of their party, said Amy Black, associate professor of political science at Wheaton College. This year, pro-life Democrats have already won special elections in Louisiana and Mississippi.

"The special elections in Louisiana and Mississippi show that traditional GOP voters are prepared to switch parties for Democrats who run as social conservatives," said Mark Silk, founding director of the Leonard E. Greenberg Center for the Study of Religion in Public Life.

Republicans were already in trouble before the special elections. More than 20 Republican members of Congress have retired since 2006, some hastened, perhaps, by the party's loss of majority status. Senate Republicans are defending 23 seats compared to just 12 for the Democrats. In addition, the Democrats have lost none of their incumbent senators.

To make matters worse for the Republicans, the Rothenberg Political Report lists only one Democratic seat, the one held by Sen. Mary Landrieu of Louisiana, as vulnerable. The report lists at least seven vulnerable seats for the Republicans. Should Obama win the presidency, he could be backed by a large House majority and filibuster-proof Senate.

"Democrats are in a position that we haven't seen in a century: to follow up a landslide victory with another, possibly even a larger one," said Eric Sapp, senior partner at Common Good Strategies, which helps Democratic candidates to engage religious communities. "That will be really significant, perhaps most importantly because the Democrats that have been winning and will be coming into Congress are much more 'faith-friendly' and tend to come from strong faith backgrounds themselves."

Common Good Strategies worked in 2006 with three victorious Democratic candidates: Sen. Bob Casey of Pennsylvania, Gov. Jennifer Granholm of Michigan, and Gov. Ted Strickland of Ohio. All three politicians outperformed the Democratic average among white evangelicals by about 17 percentage points. And each candidate's Republican opponent was a noted social conservative.

The Democratic openness to faith comes at the same time Republicans want to prove they are not beholden to the Religious Right, Silk said. But he noted that there is still time for the political terrain to shift.

Same-sex marriage nearly disappeared as an election issue in 2006, after playing a key role in 2004. However, Wheaton's Black said the recent ruling by the California Supreme Court to overturn a ban on gay marriage might elevate the issue once again for social conservatives.

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"Spoils of Victory," about evangelical voting patters in 2006, said pro-life Democrats hoped the party's takeover would remove the stereotype of Democrats as social liberals.

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