JUNEAU, Alaska (AP) — Republican U.S. Sen. Dan Sullivan is running for reelection in Alaska and faces a field of 15 competitors. One of them is Dan Sullivan.

The senator told reporters in Washington, D.C., on Tuesday that he thinks the appearance on the state’s primary ballot of another Republican with the same name is a dirty political trick coordinated by Democrats and the campaign of his chief rival for the seat, former Democratic U.S. Rep. Mary Peltola. He threatened a lawsuit to get to the bottom of it.