10 most interesting showdowns in 2010
GOP tries to play 41-seat pickup
10 Senate seats most likely to flip
Economy key to midterm trends (by Charles Franklin)
Off-year elections offer lessons
Past may be prologue for congressional races
and
Some thoughts from Chuck Todd and friends on nationalizing the elections. Of course, nationalizing the midterms comes at the cost of tailoring campaigns to local conditions and might hurt the Democrats.
Also, wrapping up the 2009 gubernatorial elections in New Jersey and Virginia, Charles Franklin shows that voting, compared to 2008, was more influenced by rightward shifts in demographic groups as opposed to changes in electorate due to turnout. The analysis is completely graphical and very clearly argued, I urge you to check it out.