Most of this is based upon recent polling data in an effort to estimate Republican gains in the Senate in 2010. Of the 37 seats up for grabs, 19 are currently held by Democrats. An analysis show the following:
Safe Democratic likely victories: Oregon (Wyden), Hawaii (Inouye), Wisconsin (Feingold), West Virgina, Maryland (Mikulski), New York (Schumer and Gillibrand), Connecticut (Blumenthal replacing Dodd) and Vermont (Leahy).
Leaning Democrat held by Democrats: California (Boxer)
Toss-up states held by Democrats- Washington (Murray), Colorado (Bennett), Illinois (Burris/Obama), Pennsylvania (Specter) and Nevada (Reid)
Seats held by Democrats they will likely lose- Arkansas (Lincoln), North Dakota (Dorgan), Delaware (Kaufmann/Biden), Indiana (Bayh)
Safe Republican victories- Arizona, Alaska, Idaho, Utah, South Dakota, Kansas, Oklahoma, Louisiana, Iowa, Alabama, Georgia, South Carolina and New Hampshire
Seats by Republicans leaning Republican- Missouri, Kentucky, Ohio and North Carolina
Seats by Republicans that are toss-ups- Florida
There are no Republican seats leaning Democratic or that they will definitely lose.
Assuming they win the four seats listed and defend all their seats, Republicans would pick up 4 seats under a sort of worst case scenario for the GOP in the Senate giving the Democrats a 55-45 margin. The real worst case scenario would be to lose Florida and have Crist caucus with the Democrats and lose the seats in Missouri, Ohio, and Kentucky. Assuming Republicans do not pick up seats anywhere else, that would maintain their 59-41 advantage in the Senate.
Based on the most recent polling data after all the July polls, however, if the elections were held today, the Republicans would pick up seats in Colorado, Pennsylvania and Nevada besides the four minimum pick ups listed above. That would give them a 7 seat pick up with the anticipated loss of Florida, based on the most recent polling data AND assuming Crist caucuses with the Democrats, Republicans would still pick up six seats while defending their vulnerable/competitive seats (Ohio, Kentucky, North Carolina, and Missouri). In a realistic sense, the outlook is a 53-47 Democratic majority.
This is not bad news for Republicans in the Senate. The better balance among the parties would create greater bipartisanship and strengthen the hand of the Republican leadership in negotiations. Assuming McConnell can keep toegther a Republican coalition, it would be almost impossible for Obama's agenda to pass without bipartisanship in the truest sense. Secondly, the gains this year set up future gains in the future where Republicans would be poised to target vulnerable Democrats in 2011 or 2012 and actually take over the Senate. This, combined with the House becoming Republican this year, would make the last years of Obama's Presidency difficult, if not impossible to enact his liberal agenda. In short, he would have to pull a Clinton and veer sharply to the center or right.
Most importantly, it is tantamount that Republicans build on their gains this year by having a clear agenda for the problems that confront this country in all areas and that bipartisan agreements with the more moderate Democrats be sought. The new Republican leadership needs to show that they can work with Democrats to solve our Nation's problems and not result to the chest-puffing tactics of the Democratic-controlled Congress under Pelosi. In short, a Republican victory in November or even gains need to met with reality and a certain sense of humility- not a proclamation of a mandate (although in reality it probably is a referendum on Obama's policies). Perception is 90% of the game and perhaps less of the cockiness of the Democratic Party is what is needed here despite the anticipated Republican gains this fall.