Fresh from his appearance at a John Locke Foundation election panel Headliner luncheon, Fred Barnes has written a new Weekly Standard feature pointing to North Carolina as the key to national Republicans’ hopes for the 2014 elections.

To win the Senate, Republicans must win North Carolina. While it’s mathematically possible to take the Senate without ousting Democratic senator Kay Hagan, the chances of that happening are close to zero. For Republicans, North Carolina is necessary. It’s the key to control of the Senate.

It’s number six on my list. That is, there are five states where capturing Democratic seats appears more likely—West Virginia, South Dakota, Montana, Louisiana, Arkansas. Then comes North Carolina. Assuming Republicans don’t lose any of their own seats, those six pickups would give Republicans a 51-49 majority. And with it, the political equation in Washington would change. Republicans would be on offense, President Obama and Harry Reid on defense.

But winning in North Carolina is no cinch for Republicans. Two facts stand out. One, Hagan is extremely vulnerable. She’s a Reid follower who voted for Obamacare and most of the president’s agenda. Two, there’s a budding consensus that State House speaker Thom Tillis is the Republican with the best chance of defeating Hagan. Democrats, including Reid, certainly think he is.

In this circumstance, touting Hagan is too tame a tactic for Democrats. So she and Reid are playing hardball, intervening in the GOP Senate primary against Tillis. In Hagan’s first ad last week, she attacked Tillis for commenting favorably on Obamacare but criticizing Hagan for voting for it. “Watch close,” the radio spot said. “Seems Thom Tillis wants it both ways.” In truth, he doesn’t. Tillis advocates repeal of Obamacare. A day before Hagan struck, Reid’s Senate Majority PAC began airing $1 million in TV ads that link Tillis to two staffers who were fired for having affairs with lobbyists. Tillis shared an apartment with one of them and both got severance pay when they were fired.