Sen. Kay HaganKay Ruthven HaganPolitics is purple in North Carolina Democrats can win North Carolina just like Jimmy Carter did in 1976 North Carolina will be a big battleground state in 2020 MORE (D-N.C.) holds a narrow lead over North Carolina Speaker Thom Tillis (R), according to a new poll conducted by the Civitas Institute, a conservative think tank in the state.

Hagan leads Tillis by 42 percent to 36 percent in the poll, with libertarian candidate Sean Haugh pulling 9 percent. When Haugh is removed, Hagan leads Tillis by 47 percent to 43 percent.

A month ago, Civitas found Tillis with a 3-point lead in the race.

This is the third straight poll to find Hagan with a narrow edge over her GOP challenger. She led in surveys from the Democratic Public Policy Polling and the Republican Magellan Strategies earlier this month.

The live-caller poll of 600 registered voters, which included a cellphone sub-sample, was conducted on June 18, 19 and 22 and has a margin of error of plus or minus 4 percentage points.

North Carolina will be a key battleground in the battle for Senate control.