So says CQ.

But defending at least four open seats in Connecticut, Delaware, North Dakota and Illinois as well as vulnerable members like Reid, Lincoln, party-switcher Arlen Specter of Pennsylvania, and two virtually unknown appointees — Michael Bennet of Colorado and Kirsten Gillibrand of New York — will be no easy task for Democrats as they seek to hold onto a commanding Senate majority next year. Republicans are defending four open seats in New Hampshire, Missouri, Ohio and Florida, giving Democrats a few opportunities to stem their likely losses.