State Sen. Carla Nelson has joined the crowded race for Minnesota's only open congressional seat.

Nelson's Monday campaign launch was overshadowed by news of the mass shooting in Las Vegas hours before. The Rochester Republican went ahead with her event but skipped her speech, offering prayers for the victims, and left the stage without taking questions.

"While I have decided to run for Congress, today is not the day for campaigning," Nelson said in a statement. "This is a solemn day for our nation, a time when we need to come together and pray for the victims of Las Vegas. … I look forward to the days and weeks to come as my campaign gears up. For now I hope everyone will continue to keep the victims, their families, and the first responders in their thoughts and prayers."

So far, two Republicans and eight Democrats are vying for the southern Minnesota seat now held by Democratic U.S. Rep. Tim Walz, who is stepping down to run for governor in 2018.

Republican Jim Hagedorn, who nearly unseated Walz in the last election, is running again. Nelson has not said whether she would abide by her party's endorsement in the race.

Minnesota's First Congressional District extends across the state's southern border, stretching from South Dakota to Wisconsin.

The district had been solidly Republican for decades, but that has changed in recent elections. In 2006, Walz defeated Republican Gil Gutknecht.

Nelson and other Republicans have reason to be optimistic. In the last presidential election, Donald Trump won the district with 53 percent; Democrat Hillary Clinton trailed with 38 percent.