Dems can hold Senate

The early 2012 conventional wisdom was that Republicans would easily take control of the Senate this November. It was a perfectly reasonable supposition — 23 Democratic seats are up for reelection, with the GOP defending just 10. Given that Republicans need a net pickup of only four seats for an outright majority, the numbers appeared to be squarely in their favor.  

But elections have a funny way of confounding even the surest predictions, and it’s increasingly evident that Mitch McConnellMitch McConnellRocky rollout for Senate healthcare bill Overnight Healthcare: Latest on Senate healthcare bill | Four conservatives say they'll oppose | Obama slams bill | Health groups offer scathing criticism Sanders: I hope McConnell listened to protesters outside his office MORE might want to hold off on ordering those new business cards.

Six of the seats where Democrats are playing defense are in red states, and one of them is Missouri Sen. Claire McCaskillClaire McCaskillSenators question need for HHS cyber office Overnight Cybersecurity: Obama DHS chief defends Russian hack response | Trump huddles on grid security | Lawmakers warned about cyber threat to election systems We must protect our most vulnerable from financial fraudsters MORE’s. McCaskill remains the most endangered Democratic incumbent, her hopes resting on a nasty GOP primary that might produce a weakened opponent. And in Nebraska, Democratic former Senator and Gov. Bob Kerrey trails badly, although he’s making Republicans spend money in a state they had chalked up in the win column just a few months ago.

But in North Dakota, where Republicans thought they had an easy pickup when Sen. Kent Conrad retired, former Attorney General Heidi HeitkampHeidi HeitkampSenate Dem undecided on 2018 reelection run Trump ‘regulatory czar’: Two-for-one rule can work Congress should just say no to more green energy handouts MORE leads in the early polling. And West Virginia’s Joe ManchinJoe ManchinZinke hits Dems for delaying Interior nominees Manchin faces primary challenge from the left Sessions sequel falls flat following Comey drama MORE is headed toward an easy reelection after narrowly winning the seat in a 2010 special election. 

The final two Democratic seats in red states, Montana and Virginia, are both neck and neck — same as they were in 2006, when their outcome decided control of the Senate. We could see a repeat this November. 

Republicans have targeted open Democratic seats in New Mexico and Wisconsin, both fiercely competitive. However, Wisconsin will be far less competitive if Republican primary voters reject their best candidate, moderate former Gov. Tommy Thompson. 

Beyond that, Republican challenges to Democratic incumbents in Florida, Michigan, Ohio and Pennsylvania all appear to be fizzling. Florida Republicans have failed to recruit a top-tier challenger to Sen. Bill NelsonBill NelsonSenate panel unveils aviation bill with consumer protections, drone fix Driverless cars speed onto political agenda Biden leaves options on table for another White House bid MORE, who has commanding leads in polling. Ditto with Pennsylvania. In Michigan, former GOP Rep. Pete Hoekstra cratered after airing a racist attack ad during the Super Bowl, and never recovered in his bid to unseat Sen. Debbie StabenowDebbie StabenowNo certainty on cost-sharing payments to insurers Dems express concerns about Trump's proposed rural development cuts Trump, Clinton campaign aides launch their own bids MORE. And in Ohio, no non-presidential candidate has faced more negative super-PAC money than Sen. Sherrod BrownSherrod BrownDems push for more action on power grid cybersecurity Senate Banking panel huddles with regulators on bank relief Overnight Regulation: Labor groups fear rollback of Obama worker protection rule | Trump regs czar advances in Senate | New FCC enforcement chief MORE, yet he has weathered at least $5 million in attacks with limited erosion in support. 

As of today, that means the GOP is favored in two states and faces toss-up battles in perhaps five more. Remember, they only need four of those to win control, but that’s assuming they don’t lose any seats.

And make no mistake — the Democrats are also playing offense. 

There’s a real fight in Massachusetts, where Republican fluke Sen. Scott Brown is facing grassroots superstar Elizabeth WarrenElizabeth WarrenLive coverage: Senate GOP unveils its ObamaCare repeal bill Overnight Regulation: Labor groups fear rollback of Obama worker protection rule | Trump regs czar advances in Senate | New FCC enforcement chief Budowsky: Dems madder than hell MORE. In Maine, left-leaning independent and former Gov. Angus KingAngus KingZinke hits Dems for delaying Interior nominees Angus King: I’m sure Flynn will 'appear before the committee one way or another' GOP senators pleased with Ivanka Trump meeting on family leave, child tax credits MORE is likely to capitalize on Republican Sen. Olympia Snowe’s retirement.

Democrats are also competitive in Nevada and Arizona, where changing demographics are transforming the political landscape. 

And then there’s Indiana, which really should be safely Republican. Yet conservatives gifted Democrats with an opening by ousting longtime incumbent Dick Lugar in the GOP primary. Democratic nominee Joe DonnellyJoe DonnellyLawmakers sport LSU gear at baseball game in honor of Scalise Senate votes to continue arming Saudis As Yemenis suffer the consequences Overnight Defense: Mattis defends Trump budget | Senate rejects effort to block Saudi deal | Boeing to cut 50 executive jobs MORE, a sacrificial lamb against Lugar, is even money against conservative darling Richard Mourdock. 

With Democrats in good position to take two Republican seats, and competitive in three more, it’s clear that the GOP’s path to the Senate majority is a whole lot more treacherous than it seemed a few short months ago.

Moulitsas is the publisher and founder of Daily Kos (