For much of this year, national Democrats have been searching for a high-profile candidate to challenge Republican Thom Tillis.
Attorney General Josh Stein said no. Former Charlotte Mayor Anthony Foxx ruled out a run today, and state Senator Jeff Jackson has so far declined to enter the race.
Cal Cunningham was running for lieutenant governor, but is switching to the Senate race.
Cunningham said he switched after being encouraged by North Carolina voters, and after meeting with the Democratic Senate Campaign Committee in Washington.
"The road kept leading back to how we deal with the biggest obstacles to solving problems here at home," he said. "Which is why we kept having conversations about the political corruption, and the fact that Washington is vastly out of touch."
The other Democrats running are Mecklenburg Commissioner Trevor Fuller and state Senator Erica Smith of Northampton County.
Cunningham of Lexington was elected to the state Senate in 2000 when he was 27. He didn't seek reelection in part due to redistricting.
After 9/11, he joined the Army Reserves and later served in Iraq as an Amry prosecutor.
He lost to Secretary of State Elaine Marshall in the 2010 U.S. Senate Democratic primary. Marshall later lost to Republican Richard Burr.
Cunningham hasn't held elected office in 17 years, but he said that won't be a problem.
"I think that voters are generally hungry for a whole diverse set of life experiences that are reflective of their life experiences," he said.
He now heads a Raleigh-based environmental consulting firm, Waste Zero.
Cunningham has raised more than $300,000 for his lieutenant governor campaign, but he can't automatically transfer that money to the Senate race. He must first coordinate any switch with each donor.
Tillis has so far attracted one primary challenger, retired Raleigh businessman Garland Tucker. Tucker has criticized Tillis for not supporting President Trump enough.