Following the Money from the Campaign Committees | Elections

"This matches up with where the committees are spending their money. The NRSC pulled out of California, tacitly conceding the seat to the Democrats, and they don't plan to do much in Delaware (the DSCC's still spending there). Similarly, the DSCC has given up on North Dakota, Indiana and Arkansas, and don't look to be competing for GOP-held seats in Ohio, Louisiana, Florida, New Hampshire or North Carolina."

http://elections.firedoglake.com/2010/10/01/following-the-money-from-the-campaign-committees/