Nebraska is not included, as Republicans will easily pick up that (vaguely) Democratic seat. The "Dem" number above for Maine is actually independent Angus King, since he has become the de facto Democrat in the race.
If the election ended today, and those poll numbers held, Democrats would lose just that Nebraska seat and pick up Arizona, Indiana, Maine, and Massachusetts, for a +3 net gain and a 56-44 Senate. Given that we entered this cycle expecting to barely hold the Senate, that this is a possibility is amazing.
Of course, there's the matter of the undecided voters in these polls, and in Senate races they tend to swing in the direction of the state's dominant political party. That's why I never worried about Elizabeth Warren in Massachusetts—as long as she had the resources to compete against Scott Brown, the state's heavily Democratic voters would likely swing in her direction (and they have been). Maine is complicated, but still, the only time Republicans win is when the state's significant independent and Democratic wings split the vote evenly. Right now, the Democrat in the race is a sideshow with much of the state's left-of-center support coalescing around King.
Nevada should technically look good, and it still might, but things are complicated by bullshit ethics issues that have dogged Democrat Shelley Berkley's campaign. She'll outperform the polls on election day because of the Obama machine, but she needs to stay close to appointed Republican incumbent Sen. Dean Heller. Connecticut's liberal leanings will close the deal for our candidate, as should Wisconsin's.
So what about Arizona, Indiana, Montana, and North Dakota? Those are all red states in which our candidate is currently leading, but below 50 percent. Yeah, those are the tough ones.
Arizona's partisan leanings would clearly give Republican Jeff Flake the advantage, yet he's failing to keep pace with the top of his ticket. I still give him the edge, but Richard Carmona is certainly coming on strong and has a legit chance of pulling it off, particularly if Latinos turn out. Heck, some polling is showing the race competitive at the presidential level which would obviously make Cardona's task easier if true.
Indiana remains the most likely to stay Red in this list. While Democrat Joe Donnelly has a narrow lead, and while Republican Richard Mourdock is embarrassingly below 40 percent, it'll be easier for the Republican to break 50 percent in a state that Obama isn't contesting this year. Still, regardless of how conservative the state might be, Mourdock's anemic numbers show that he's a poor fit for the state. It shouldn't even be competitive, so it's wonderful seeing Republicans dump money into a state that would've been a default hold if the teabaggers hadn't ousted Sen. Dick Lugar in their primary.
North Dakota should be a tough hold in this open-seat race, but Democrat Heidi Heitkamp is hovering just below the 50 percent mark in a state small enough where retail politics matters. And she's good at the retail politics.
Finally, Montana is a real dogfight with two statewide-elected members of Congress—Democratic Sen. Jon Tester and Republican Rep. Danny Rehberg, who represents the state's sole House seat. While Obama isn't contesting the state (he lost it by just 49-47 in 2008), it's more purplish than true Red, and Democrats are competitive at all levels of government. So while Rehberg should get a slight partisan advantage, the fact that he is a well-known drunk asshole could do him in. Still, expect this to be the last Senate race called on Election Night. Just like in 2006.
If I had to guess today, I'd say the Dems end up losing that single seat in Nebraska, while picking up Maine, Massachusetts, and Nevada for a net gain of two seats. But the picture is definitely in flux.
Finally, let's play the "how many candidates break 45 percent" game. For Republicans, it's two of 17. For Democrats, it's 12 of 17. Just like Romney, their Senate candidates are finding it really difficult to get out of the mid-40s.
The big mystery: why aren't we seeing similar GOP difficulties in the House? What makes the GOP brand so toxic at the presidential and Senate levels, but not in the battle for the House? Gerrymandering is the obvious answer, but that wouldn't explain the slight Democratic edge in the generic congressional ballot polling. I'm perplexed.
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