Ignore anyone who says Republicans have no chance of winning 40 seats in next year's midterm elections and grabbing control of the House of Representatives. A landslide of that dimension is quite possible. All it would take is for current political trends to continue. If that happens, Republicans will win the House in a landslide. The Senate is another story.

The deep trouble that's beginning to engulf Democrats is now an inescapable fact of political life. With the congressional election 13 months away, Democrats have time to halt their decline and prevent a Republican surge. But they've shown no signs of reversing their slide. In 2006 and 2008, they were on offense. Today they're stuck on defense.

Predicting the outcome in 2010 is partly guesswork. The political climate, the number of open seats, and the quality of candidates a year from now--those are unknowns. Nonetheless, a strong drift toward Republicans is clear. If the election were held today, the best guess is Republicans would win 15 to 25 House seats.

Democrats can point to successes. Their fundraising matches or exceeds that of Republicans. Voter registration has tilted in their favor. And they've won impressive majorities among young voters, Hispanics, and the highly educated in the past two elections.

But those are lagging indicators. In looking to 2010, it's the leading indicators that matter, and Republicans are doing extraordinarily well in all of them. Let's take a look at five of these indicators.

Two are especially significant: the so-called generic ballot and presidential approval. Political scientist

In polling, the generic question asks which party respondents intend to vote for in the next election. Republicans trailed Democrats for most of 1994. "When we took the lead, we took the majority in the House," says California Republican representative Kevin McCarthy, the chief recruiter of candidates for House seats.

For the 2010 cycle, Republicans are already in the lead. In the Rasmussen poll, Republicans jumped narrowly ahead of Democrats last spring for the first time since 2004. And they've held their lead. Last week, they topped Democrats by 42 percent to 40 percent.

Meanwhile, President Obama's approval ratings have fallen precipitously. In the Gallup poll, he began his presidency with 68 percent approval. Now his rating hovers in the low 50s. In last week's Fox News poll, Obama's approval was 50 percent. Several polls have put it briefly in the high 40s.

The 50 percent level is important. The history of midterm elections suggests that Republican gains will be held to the post-World War II average of 26 seats or fewer if Obama can keep his approval in the 50s. If it dips to the low 40s, that correlates with a pickup of roughly 40 seats by Republicans, giving them a majority in the House.

Based on his forecasting model (and using current political trends), Abramowitz says Democrats are likely to lose at least 15 House seats in 2010 "and their losses could go as high as 30-40 seats." A loss of 3 to 4 Senate seats--which would mean a Republican gain of 3 to 4 seats--is "entirely possible," he says. Should Obama's approval recover and reach the 60s and Democrats go ahead on the generic ballot, Republicans would win 15 seats in the House while losing a Senate seat, according to Abramowitz.