Nevada Representative Joe Heck filed paperwork today to run as a Republican candidate to replace Sen. Harry Reid, who's held the seat for three decades.
Heck announced his intent to run for senate last summer, but Monday's filing made it official.
The doctor and one-star general will face off against former state attorney general Catherine Cortez Masto, who plans to file March 15.
It's one of several key races in battleground states that Democrats hope to win in order to regain control of the Senate.
Fred Lokken, a political science professor at Truckee Meadows Community College, says he expects Sen. Reid to be heavily involved in trying to get Masto to become his successor.
"So he's going to be, I think, more involved in Nevada politics for the Democrats in 2016 than he has in recent cycles,” says Lokken. “[N]ot only will that be of benefit for her candidacy, but I think it will also see a real uptick in fundraising for all of the state offices that are going to be in the race."
Heck has represented Nevada's 3rd congressional district in the southern part of the state since 2011. Before that he served as a state senator for four years.