“There’s a sense building among Republicans that 2010 is going to be a far better political environment than 2008 or 2006,” said GOP pollster Whit Ayres. “Part of that is because we have a Democratic president and a Democratic-controlled Senate and House that are promoting fiscally dangerous policies for the future of the country. Part of it is we don’t have the burden of Iraq as we did in 2006 and don’t have the economy on the Republicans’ watch as we had in 2008.”…

The polls tell only part of the story. National Republicans have recently met with success in persuading a number of top recruits to commit to 2010 races that not so long ago looked considerably less attractive — the surest signal that potential GOP candidates view the playing field as less tilted against them than just a few months earlier…

Because of GOP retirements in key battleground states, Republicans will be fortunate just to hold down their losses in the Senate next year. Still, if nothing else, the outlook is not nearly as grim as in January, when Republicans were poised to defend 19 seats to just 15 for the Democrats.

Now, as a result of Obama’s and Vice President Joe Biden’s resignation from the Senate, and the appointment of two Democratic senators to Cabinet positions, both parties are now defending 18 seats each in 2010 — with Democrats defending four seats now held by appointed senators that suddenly look more competitive than they would have been otherwise.