While the midterm elections are still more than a year away, Republicans are beginning to lick their chops as rising unemployment rates, a record federal deficit and President Obama's slipping support signal possible double-digit losses for Democrats in the House and key defeats in the Senate.

Democrats, facing the most politically toxic environment since 1994, currently have a 256-178 edge in the House, with one vacancy, and 58-40 edge in the Senate, with two Independents who vote with Democrats.

Since the mid-19th century, the party that controls the White House has lost seats in virtually every midterm election except 1934, during the Great Depression, and 2002, following the Sept. 11 terrorist attacks.

Republicans would have to pick up 40 seats in the House to regain control and 21 in the Senate. While that remains unlikely, Republicans are targeting seats that they haven't pursued in decades. That includes seats held by Democratic leaders whose approval ratings are plunging according to polls.

If Republicans can land knockout blows on these leaders, it would shake up the Democrats' landscape and galvanize their party after two consecutive dispiriting electoral defeats.

Isaac T. Wood and Larry J. Sabato of the University of Virgina's Center for Politics predicted that Republicans will gain between 20 and 30 seats in all 435 House races and noted the GOP has been "drawing rave reviews for its candidate recruitment, fielding A-list challengers against many of the most endangered Democratic incumbents."

On the Senate side, the biggest targets for Republicans are Senate Majority Leader Harry Reid of Nevada, Christopher Dodd of Connecticut, Barbara Boxer of California, Blanche Lincoln of Nebraska.

Click here for a look at seven of the biggest Democrats facing the biggest threats in the upcoming elections.