With a generous tip of the hat to Kirsten for the link, here is a four-fold map of projected House, Senate, and gubernatorial races for this year, plus the results from the 2004 Presidential election. One of the things I found interesting as I looked over the various permutations and distinctions and so on, was the predominance in Senate races in states that went to George W. Bush in 2004, of leaning or favored Democrats, including Virginia, Florida, Louisiana, New Mexico, Colorado, Indiana, Ohio, Nevada, Arizona, Missouri, Iowa, Florida, and West Virginia. While it is usually considered good form for down-ticket candidates to attach themselves to their party's candidate for President (if he is popular) as a boost in chances for winning an election, I think it might be possible that, this year, Obama might benefit from tying himself closely with various down-ticket candidates across the country, and benefit from their popularity.
Just a thought.