Democrats are dreaming of taking over the Senate and winning in red states from Iowa to Alaska. Chris Pappas wants to make sure they don’t forget about New Hampshire.

Pappas, a four-term congressman, is the party’s consensus candidate to succeed retiring Sen. Jeanne Shaheen in New Hampshire — one of the party’s consistent bright spots during a decade dominated by Donald Trump. And Pappas is raising the alarm that his sleeper race is about to wake up.

“There are a lot of states that have come on the map over the last year and a half, which is positive. But we just can’t take our eye off of the Georgias, Michigans, and New Hampshires that are necessary to win,” Pappas told Semafor. “No one should be overconfident. This is a tough, tight race.”

There are myriad reasons why New Hampshire could be a nail-biter. With President Donald Trump’s help, Republicans successfully recruited former Sen. John E. Sununu, R-N.H, a scion of one of the state’s first families. The Senate Leadership Fund super PAC has $17 million in TV reservations this fall, and the Koch-backed Americans for Prosperity Action super PAC has already plowed $2 million into the race.

More GOP spending could follow in a state relatively cheaper than other battlegrounds.

All this is happening while polls show a single-digit race between Pappas and Sununu — sometimes as close as just a two-point lead for the Democrat. GOP leaders see New Hampshire and Michigan as perhaps their most fertile pickup opportunities, given the party’s uncertain prospects in Georgia, and are taking the Senate race much more seriously than the past two cycles.

The GOP’s chances in the state are “very good,” Senate Majority Whip John Barrasso, R-Wyo., told Semafor. Sarah Scott, AFP’s deputy director in New Hampshire, said they “really are committed to John Sununu, and believe that he’s the best candidate for us to put forward and to actually make change in Washington.”

“The Republican Party has put a lot more resources in than they have in past cycles, and they’ve obviously recruited somebody with the kind of name ID that is a threshold to success,” Sen. Maggie Hassan, D-N.H, told Semafor. “This is a really serious race.”

To be sure, Pappas has strategic advantages. It’s been a full 16 years since Republicans won a Senate race in New Hampshire, and the congressional delegation turned all Democratic a decade ago, even as Republicans held the governor’s office.

Democrats settled on Pappas more than a year ago, betting on the young, battle-tested congressman. The Democratic Senate Majority PAC has $10 million reserved in TV ads and more for digital; spokesperson Lauren French called Pappas “exactly the right candidate to win this race.” Sununu is also facing a primary challenge from former Sen. Scott Brown, who represented Massachusetts and argues Sununu doesn’t fit New Hampshire’s independent mold.

Pappas said that Brown is “outworking” Sununu but that he “would be shocked if Sununu is not the Republican nominee” because of Trump’s endorsement.

And Democrats contend the Sununu name is so strong in New Hampshire that it even obscures who exactly is on the ballot: not former Gov. Chris Sununu, but his brother.

Usually, Hassan says, Granite Staters correct each other: “Somebody will hear something and say, ‘No, you idiot, it’s the brother.’”

“There is Sununu confusion,” Pappas agreed.

He’s betting the state’s uber-sophisticated voters will “see that [John Sununu is] a different person.”