2010 Senate Rankings, Part I: Races #21-#35

At least 35 seats will be contested for the United States Senate in November, 2010, including 34 seats whose six-year terms are set to expire and one special election in Delaware (although Barack Obama's seat in Illinois will also require a replacement, it was set to expire in 2010 anyway). These include a number of tremendously interesting races, with many incumbents vulnerable to retirement or unusually strong challengers, and it is not inconceivable that as many as 15 or 20 races may wind up being seriously contested.

My feeling is that it is never too early to begin looking at these races. For one thing, I want to make it clear that FiveThirtyEight will be a presence on the political scene for a long time to come. For another, the competitive nature of some of these races may begin having implications almost immediately. For instance, if Arlen Specter believes he is vulnerable to being unseated in Pennsylvania, he may be more likely to side with the Obama administration on something like a cloture vote. Conversely, if Byron Dorgan thinks he is at risk in North Dakota, he might be more inclined to buck the new president. There are also a number of cases -- such as Washington on the Republican side or Oklahoma for the Democrats -- where if the opposition is thinking about mounting a serious challenge, it had better get started building infrastructure right away.

The races are ranked from 1 to 35 in order of their likelihood of changing hands to the opposition party. In some cases, this is a difficult calculation to handle because of uncertainty about whom the candidates might be. For instance, if Chuck Grassley decideds to run for re-election in Iowa, he is almost certainly safe, but if he retires, the seat probably leans Democrat. We have tried to reconcile these contengencies the best we can.

Where an incumbent is running, we have listed his approval, favorability or job performance ratings as compiled from recent surveys. Keep in mind that job approval scores vary heavily from survey to survey depending on question wording and are at best a rough guide to a congressman's standing.

Today, we will cover races #21 through 35.

35. Idaho (R-Crapo)

Approval/Favorability Ratings: Mike Crapo (R)
Poll               Date    Approve   Disapprove    Net
SurveyUSA          7/2007    61          26        +35

Idaho may be turning blue very, very slowly, and perhaps Walt Minnick can make a credible run at Jim Risch's newly-minted seat in 2014. But with Democrats just having lost an open-seat race by 24 points, they're not yet in any sort of position to take a run at a popular incumbent.

34. Alabama (R-Shelby)

Approval/Favorability Ratings: Richard Shelby (R)
Poll               Date    Approve   Disapprove    Net
SurveyUSA          10/18     61          32        +29

There's an outside chance that the well-liked Shelby could retire, but Alabama is one of those places where the Solid South is waning faster than the New South is waxing, and I just can't imagine the sort of Democrat who would be capable of winning a senate seat right now.

33. Utah (R-Bennett)

Approval/Favorability Ratings: Bob Bennett (R)
Poll               Date    Approve   Disapprove    Net
Dan Jones          1/2007    67          18        +49

The Democrats might have just a glimmer of hope in the form of Jim Matheson, the Democrat who represents Utah's 2nd Congressional District, who could theoretically make a run at things were Bennett, who will be 77 in 2010, to retire. But there's no indication that Bennett will do so, nor that Matheson would be ready to risk his House seat, and even then a generic Republican like Lieutenant Governor Gary Herbert would probably beat him.

32. Oregon (D-Wyden)

Approval/Favorability Ratings: Ron Wyden (D)
Poll               Date    Approve   Disapprove    Net
SurveyUSA         10/18      54          34        +20

Wyden is a popular and effective senator, and Oregon, after some flirtation with battleground state status, now appears to be back firmly in the blue camp. The GOP has better places to invest resources.

31. Indiana (D-Bayh)

Approval/Favorability Ratings: Evan Bayh (D)
Poll               Date    Approve   Disapprove    Net
SurveyUSA          2/4       58          32        +26

The Bayh brand name is probably untouchable, and having a Democrat in this seat no longer seems like such an outlier now that Barack Obama carried Indiana on Election Day. Republican hopefuls will probably wait until Richard Lugar's possible retirement in 2012.

30. Vermont (D-Leahy)

Approval/Favorability Ratings: Pat Leahy (R)
Poll               Date    Approve   Disapprove    Net
Research 2000      10/2007   67          29        +38

Some Republicans think that Governor Jim Douglas, who was just re-elected to his fourth two-year term, could be viable if Leahy were to retire, but Leahy probably has at least one more term left, and even then Peter Welch or perhaps Howard Dean would be formidable opponents.

29. New York (D-Schumer)

Approval/Favorability Ratings: Chuck Schumer (D)
Poll               Date    Approve   Disapprove    Net
Marist             10/22     55          33        +22
SurveyUSA          10/18     60          31        +29
Quinnipiac         8/2       61          23        +38

It's possible that this race could attract Rudy Giuliani or George Pataki, but they'd likely be running a fool's errand against Schumer, who is quite popular in his home state and could raise virtually unlimited amounts of money. More likely, the Republicans will want to concentrate their resources on the governor's race.

28. Maryland (D-Mikulski)

Approval/Favorability Ratings: Barbara Mikulski (D)
Poll               Date    Approve   Disapprove    Net
SurveyUSA          11/2006   57          35        +22

Were Mikulski to retire, the Republicans could think about running Michael Steele or Bob Ehrlich, but with both having lost statewide races in 2006 against fairly marginal Democrats, that probably gives you an indication of how such a challenge would resolve itself.

27. South Dakota (R-Thune)

Approval/Favorability Ratings: John Thune (R)
Poll               Date    Approve   Disapprove    Net
Mason-Dixon        10/14     64          34        +30

There's no reason to think that Thune should be vulnerable in the first place, and were something unexpected to happen -- like Tom Daschle deciding he wanted a re-match -- the Republicans would throw tons of money at the race to protect one of the few rising stars in their party. The other long-shot scenario is that Thune decides he wants to run for governor to gain some executive experience prior to a prospective White House run in 2012 or 2016, in which case Stephanie Herseth-Sandlin might try her luck.

26. North Dakota (D-Dorgan)

Approval/Favorability Ratings: Byron Dorgan (D)
Poll               Date    Approve   Disapprove    Net
SurveyUSA          11/2006   75          21        +54

Theoretically, a red-state seat like this is always vulnerable given the right Republican challenger, but Dorgan is very popular and is the sort of incumbent who President Obama will be trying to make look good. Governor John Hoeven may eventually be a problem for Democrats once he picks his year to run for the Senate, but he resisted such overtures in 2006 and may wait until the Republican brand is in better shape.

25. Washington (D-Murray)

Approval/Favorability Ratings: Patty Murray (D)
Poll               Date    Approve   Disapprove    Net
Strategic Vision   11/1      55          37        +18
SurveyUSA          10/18     55          35        +20

Murray's approval ratings are good but not great; she might be vulnerable against the perfect opponent running a pitch-perfect campaign. But there's no particular indication about whom that opponent might be. WA-5's Cathy McMorris Rodgers may eventually be an interesting candidate, but probably needs more seasoning.

24. Hawaii (D-Inouye)

Approval/Favorability Ratings: Daniel Inouye (D)
Poll               Date    Approve   Disapprove    Net
SurveyUSA          11/2006   68          26        +42

Inoyue is the more popular of Hawaii's two very popular Democratic senators, but he'll also be 86 years old in 2010. If he's unable or unwilling to run, governor Linda Lingle might have a chance at the seat. Barack Obama, however, could probably go a long way toward quashing her hopes if forced to rally for a Democrat like Mazie Hirono in his home state.

23. South Carolina (R-DeMint)

Approval/Favorability Ratings: Jim DeMint (R)
Poll               Date    Approve   Disapprove    Net
SurveyUSA          2/19      49          37        +12

DeMint is not terrifically popular and may be too conservative even by South Carolina standards. But as evidenced by their inability to nominate a credible opponent against Lindsay Graham, Democrats have real recruitment problems in this state.

22. Wisconsin (D-Feingold)

Approval/Favorability Ratings: Russ Feingold (D)
Poll               Date    Approve   Disapprove    Net
Strategic Vision   11/1      57          33        +24
SurveyUSA          10/18     53          43        +10
WisPolitics.com    6/9       59          29        +30

Feingold is the sort of liberal icon whom the Republicans are always going to want to target; the problem is that he's become something of a Wisconsin icon too. If Tommy Thompson runs and there is some perception that the Obama government has overreached, he could be vulnerable; otherwise, probably not.

21. Oklahoma (R-Coburn)

Approval/Favorability Ratings: Tom Coburn (R)
Poll               Date    Approve   Disapprove    Net
Sooner Poll        7/21      59          24        +35

The survey you see above was a Republican-affiliated poll that probably exaggerates Coburn's favorability ratings, but this remains a tough state for Democrats. Democratic governor Brad Henry, however, will be term-limited in 2010 and could decide to run for the seat. Howard Dean should be looking for a commitment from Henry sooner rather than later, because while this one is winnable if Henry is the candidate, it will require some real tender loving care.