UPDATE: 9:39 AM EST. Connecticut Attorney General Richard Blumenthal will seek Chris Dodd's seat, reports the New York Times.
As a result, Connecticut has been demoted further to 15th on our Senate race rankings. Public Policy Polling had a poll in the field this weekend, which has yet to be released but which will report that Blumenthal's entry will make the seat "uber safe" for Democrats. In addition, previous polling from Quinnipiac had found Blumenthal with exceptionally strong numbers -- a 79/13 (!) approval rating as of July -- and running well in prospective horse-race match-ups.
Original story, revised as of 9:30 AM EST. FiveThirtyEight had an early bedtime last night, and since senior Democrats are retiring at a rate of approximately one every three hours, we missed the news that Chris Dodd would also be retiring. But obviously, this news is of a vastly different character than the earlier announcement that Byron Dorgan would not seek re-election.
Dodd's problems were mostly his own, and pre-dated any issues that the Democrats were having with the national environment. I had suggested way back in April, at which time Dodd's approval ratings were already in the red, that the Democrats ought to consider primarying or Bunninging him. Although there had seemed to be some chance that Dodd's problems were mostly attributable to the AIG bonus scandal, a matter over which public anger has somewhat dissipated and for which Dodd was somewhat unfairly blamed, his approval ratings had yet to really recover and his problems now appear to be more general, stemming from a variety of controversies relating to his roles and relationships with companies tied to the financial bailout, as well as perhaps an ill-advised run for President in 2007-08 that most Connecticutians found pointless.
The remaining Democratic challenger for the moment is Merrick Alpert, who has quietly run a competent campaign but lacks experience and had only achieved 4 percent name recognition with Connecticut's voters. However, the Democrats have a deep bench in Connecticut, including attorney general Richard Blumenthal, who according to an upcoming poll by Public Policy Polling, would make the seat "uber safe" for Democrats, as well as Joe Lieberman foil Ned Lamont (who was thought likely to run for governor, but could re-consider), as well five U.S. Representatives, most notably the popular progressive Rosa DeLauro.
Any of those people, as well as possibly Alpert, would be a favorite against the Republican field, which consists of a decent-to-good candidate in former U.S. Rep Rob Simmons, as well as a number of vanity candidates who would likely be problematic nominees.
Connecticut drops, for the time being, to 12th on our Senate rankings list; it may drop another couple positions if someone like Blumenthal or DeLauro enters, and it may drop or rise depending on the performance of Martha Coakley in neighboring Massachusetts in the special election later this month.
It would be too convenient to suggest that Democrats are better off than they were 24 hours ago -- although it's somewhat close. I had thought that Democrats had a 50-60 percent chance of losing the Connecticut seat; I would now put those odds at more like 20-30 percent, pending further developments (EDIT: with Blumenthal's entry, probably more like 10-20 percent). On the other hand, while I had thought that they only had about a 20 percent chance of losing in North Dakota (much higher if John Hoeven had entered, but that was highly uncertain), those odds would now seem to be 75-80 percent or higher.