With 49 days until Election Day, the race for control of the Congress remains as murky as ever, as Republicans hopes to take over the Senate are cloudy at best.

The GOP remains the favorite to stay in power in the House, though Democrats keep talking a good game about winning more than two dozen Republican seats in Novmeber.

In terms of history, Republicans could be expected to give back some of the big gains they made in the mid-term elections of 2010 - but the shift in some seats thanks to redistricting has many experts thinking that John Boehner will stay as Speaker.

The big battle is for the Senate, where for a second straight election, Republicans have the chance to win control, but once again, some think they could fall short.

Republicans need to win over four seats to get a 51-49 majority; if the GOP gains three seats, then control of the Senate would depend on who wins the White House, as the Vice President would cast the tie breaking vote.

There are about a half dozen seats that are seen as toss ups right now:

Connecticut - Republican Linda McMahon (of WWE fame) was easily defeated here two years ago, but is back and doing better in the polls against Rep. Chris Murphy. This state should go easily for Obama, and that's why Democrats remain upbeat even as the polls are close.

Indiana - This is a GOP seat right now, as state Treasurer Richard Mourdock tries to keep it on the Republican side in a tight race against Rep. Joe Donnelly, a more moderate Democrat in Congress.  This state should flip back from Obama to Romney at the presidential level.

Massachusetts - GOP Sen. Scott Brown is running hard to keep this seat, which was once held by Sen. Ted Kennedy. Polls have shown Brown ahead by a few points or behind by a few to liberal favorite Elizabeth Warren.

Montana - Sen. Jon Tester is trying to keep Rep. Denny Rehberg (R) from moving across the Capitol. This race has been close since the start and is likely to stay that way for the next seven weeks.

North Dakota - Republicans thought North Dakota would be a slam dunk when Sen. Kent Conrad announced his retirement, but it hasn't been that way. Rep. Rick Berg (R) is getting a spirited challenge from a former state Attorney General, Heidi Heitkamp (D).

Virginia - Another race that has been very, very close is in the Old Dominion, where Republicans hope to take this seat from the Democrats; recent polls have been on both sides, or a tie. How the race for the White House shakes out in Virginia could well determine where this race goes.

Republicans also think they already have two seats won in the Senate:

Wisconsin - Republicans believe this is one they can count on, as former Gov. Tommy Thompson tries to win a Democratic seat, facing Rep. Tammy Baldwin.

Nebraska - Former U.S. Senator Bob Kerrey (D) seems to have little chance to stop the GOP here, as outsider Deb Fischer is the favorite to move this seat into the Republican column.

Not on the list of toss up races are three races that Republicans thought they could definitely win, in Florida, Ohio and Missouri.

Missouri remains an advantage for the Democrats, after the furor over comments by Rep. Todd Akin (R), as Sen. Clare McCaskill, once seen as the most vulnerable Democrat in the Senate, now is in a much stronger position.

In Florida, Sen. Bill Nelson has kept a solid lead in the polls over challenger Rep. Connie Mack; in Ohio, the race has widened a bit in recent days in favor of Sen. Sherrod Brown over Ohio Treasurer Josh Mandel.

Democrats also still think they have a chance in Nevada and Arizona, though the polls remain on the GOP side, though not by large margins.

Can Republicans win a net of four seats or more to take the Senate?

We will know in seven weeks.