10 states that could decide the next Senate

The Senate map for 2016 might not be as bad for Republicans as it looks.

The GOP has a bigger cushion than expected for its new majority, probably 54 seats. More veteran senators may stick around to preserve safe seats. And some vulnerable incumbents will have committee chairmanships that could pump up their profiles.

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Even though conventional wisdom suggests this may be a short-lived Republican majority, interviews with nearly two dozen operatives in Washington and 2016 battleground states reveal a more nuanced picture of the next Senate landscape. The most vulnerable Democrats this year were up in very red states; the most endangered Republicans in 2016 will, with the exception of Illinois, be defending seats in purple terrain.

Three sitting Republican senators begin the cycle as underdogs: Wisconsin’s Ron Johnson, Illinois’ Mark Kirk and Pennsylvania’s Pat Toomey. Obama carried each of these states by at least 5 points in 2012, and there are credible challengers who will likely take little coaxing to get in. The only truly endangered Democratic incumbent is soon-to-be Senate Minority Leader Harry Reid of Nevada.

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Democrats are already eyeing several 2014 losers — or likely losers — to give it another go in 2016. Among them are Sen. Kay Hagan (D-N.C.) to challenge Republican Sen. Richard Burr, or Louisiana Sen. Mary Landrieu to run for Republican David Vitter’s Senate seat should he be elected governor.

Former Democratic Senatorial Campaign Committee Executive Director J.B. Poersch said that, while Democrats should take heed of what went wrong this year, “it is an encouraging map” and “it should be a better electorate.”

Indeed, the GOP must defend seats in seven states that President Barack Obama carried twice. But former National Republican Senatorial Committee Executive Director Rob Jesmer believes Republicans will retain the majority if the party nominates a credible presidential candidate who can stay competitive in purple states, even if that person doesn’t win.

“I worry more about who our nominee is going to be than I do about the map,” Jesmer said.

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What follows is POLITICO’s first snapshot of the 2016 Senate landscape, looking at the 10 most competitive seats in the order of most to least likely to change parties.

Wisconsin

First-term Republican Sen. Ron Johnson won his seat in one of the biggest surprises of the 2010 tea party wave, beating Democratic Sen. Russ Feingold. A rematch could be in store.

Johnson, a wealthy businessman who self-financed his first campaign, has not moved to the center during his term and a Marquette University poll last month had him with a worrisome 33 percent favorability rating. That could mean trouble in 2016. Though Gov. Scott Walker just won his third statewide race in four years, the Badger State likes Democrats in presidential years. Ronald Reagan was the last Republican presidential nominee to carry the state.

Wisconsin Democrats say Feingold, currently a State Department liaison to Africa, is the likeliest challenger and could probably clear the field. Rep. Ron Kind has long eyed statewide office, but progressives view him skeptically. Mary Burke said Monday she will not run for statewide office again after losing to Walker.

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But Johnson won’t be easy to beat: He spent $9 million of his own money in the 2010 race, and there’s more where that came from. Plus, he’s a favorite of the Koch brothers’ donor network. Operatives tied to the groups say they are likely to spend heavily on his behalf.

Pennsylvania

Another potential rematch here: Freshman Republican Sen. Pat Toomey is likely to square off against former Democratic Rep. Joe Sestak, who signaled more than a year ago that he intends to run.

Sestak, who toppled party-switcher Arlen Specter in a 2010 primary despite the opposition of Obama and the entire Democratic establishment, is still not a favorite of Keystone State party bosses, but it’s unclear whether anyone will take him on.

“I intend to sail in harm’s way,” the retired admiral wrote in an email to his fundraising list last week.

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Toomey, who once ran Club for Growth, knows he’s vulnerable in a presidential year (George H.W. Bush was the most recent Republican to carry the state, in 1988). Unlike Johnson, he has made efforts to move to center, co-sponsoring a background check bill last year, for example. Still, Quinnipiac pegged his approval rating at 41 percent in June.

The other Democratic name mentioned most often in connection with the Senate seat is Attorney General Kathleen Kane, but sources say she’s likely to opt for coasting to a second term in 2016.

“A couple of people who ran for governor last time may look at it again, but none of them ran a particularly good race,” said a top Washington Democrat, referring to the state’s crowded Democratic gubernatorial primary this year.

Illinois

Republican Sen. Mark Kirk, a moderate from suburban Chicago, narrowly won his seat in 2010. He has told colleagues that he plans to run again, GOP sources said, despite ongoing rehab for a stroke.

If he changes his mind, it would give Democrats a near-certain pickup. But Republicans have a fight on their hands here even if Kirk runs again. The Democrat mentioned most as a potential challenger is state Attorney General Lisa Madigan, though she might prefer to take on GOP Gov.-elect Bruce Rauner in 2018.

Another Democrat to watch here is Rep. Tammy Duckworth, an Iraq War veteran and Purple Heart recipient who served as an assistant secretary of the Veterans Affairs Department before winning her House seat in 2012. A few Democrats in the state’s House delegation and Cook County Sheriff Tom Dart will also take a look at the race, according to a Democratic power broker in Washington.

Nevada

Just how vulnerable Reid is...