What just a week ago looked like an intriguing match-up between Indiana Sen. Evan Bayh, a Democrat, and former Republican Sen. Dan Coats has now changed dramatically (if temporarily) with Bayh's announced retirement.
Bayh had entered the year as a proven winner even against a tough GOP headwind, having won re-election in 2004 with 62 percent of the vote while George W. Bush was handily taking the state that year. Without him or a ready-made successor in the race, Coats stands as a known name in Indiana politics, who has won statewide office here - a starting position most would envy.
Thus Indiana – pending the parties' primaries, and who'll take Bayh's spot as the Dem nominee – for now joins Delaware and North Dakota as states where the GOP is eyeing pickups, and could do so in contests not quite as heated as some other states.
The hottest contests still look like they'll take place in 5 Democratically-held seats, 3 Republican-held; the latter (Missouri, New Hampshire and Ohio) could be competitive especially because there's no incumbent to help the GOP defend the seat. Included on this list are some very high-profile incumbent names like Harry Reid of Nevada, and Blanche Lincoln of Arkansas who'll fight to keep a seat in a state that went Republican handily in '08.
The hottest races:
|Illinois||D-Open (Current: Roland Burris)|
|Missouri||R-Open (Current: Kit Bond)|
|Nevada||D - Harry Reid|
|New Hampshire||R-Open (Current: Judd Gregg)|
|Ohio||R-Open (Current: George Voinovich)|
|Pennsylvania||D - Arlen Specter|
Less competitive, but with potential Dem to Rep turnovers:
Three Democratic-held seats aren't as competitive, but the GOP is eyeing pickups. These will warrant close watching over the spring to see how Democratic candidates and campaigns shake out. Indiana is now on this list as vulnerable to the GOP.
|Indiana||D-Open (Current: Evan Bayh)|
|North Dakota||D-Open (Current: Byron Dorgan)|
|Delaware||D-Open (Current: Ted Kaufman)|
Five other states could become very competitive too -- two Democratic-held and 3 Republican-held. Democrats have an electoral edge in California and Connecticut while Republicans hold one in Louisiana and North Carolina, but these states could still see heated contests.
|Connecticut||D-Open (Current: Chris Dodd)|
|Florida||R-Open (Current: George LeMieux)|
|North Carolina||R-Richard Burr|
Other states currently worth watching include Kentucky -- where Democrats could challenge for an open Republican-held seat but the GOP holds an electoral edge going in -- and New York, where a potential primary and long primary season could change the overall dynamic. But these and many others will have to await challenger candidate selection, and, of course, some time.
Anthony Salvanto is CBS News Elections Director. Mark Gersh is Washington Director, National Committee for an Effective Congress, and a CBS News Consultant.