Democratic Sen. Heidi Heitkamp's path to re-election in North Dakota will get tougher on Friday evening.
The state's lone congressman, Rep. Kevin Cramer, a favorite of Republican leaders, is set to announce his bid for Heitkamp's seat in November's midterm elections. Cramer initially declined to run, and his expected campaign bolsters Republican hopes of taking the seat in a state President Donald Trump won easily in 2016.
Cramer's entry helps the GOP's chances of either holding on to or expanding its 51-seat majority in the Senate. Heitkamp, currently serving her first term, is one of several Senate Democrats defending seats later this year in states Trump carried.
Cramer's expected bid led election ratings site Sabato's Crystal Ball to change the North Dakota race from "leans" Democratic to a "toss-up." The third-term congressman has proven a reliable Trump ally in the House and helped to craft his energy policy during the 2016 election.