Walsh had 64 percent of the vote to 23 percent for former Montana Lt. Gov. John Bohlinger (D) and 10 percent for wealthy rancher Dirk Adams (D), with 7 percent of precincts reporting. Daines had 85 percent of the vote against two little-known opponents with 7 percent of precincts reporting.
Daines begins the general election as the favorite against Walsh and has led the recently appointed senator by double-digit margins in most public polling in the Republican-leaning state.
Both candidates trumpeted their wins and wasted no time attacking one another in what's already been a negative campaign.
"Today, Montanans sent a clear message that they are ready to change Washington and fight for more jobs, and less government. Montanans can no longer afford a U.S. Senate – or an appointed Senator— that follows President Obama and rubber-stamps failed policies like Obamacare, job-killing energy regulations, and trillions of dollars in wasteful Washington spending," Daines said in a statement.
"Every day I hear from seniors threatened by a Congressman who has tried twice to privatize their Medicare. I hear from parents with full-time jobs who still struggle to feed their children; from veterans who cannot access the health care services they were promised; and from women who worry that Washington politicians will take away their right to make their own health care decisions," Walsh said in a statement. "We know what’s at stake with this election, and we will keep holding broken Washington — from our own Congressman to the White House — accountable."
In Montana's at-large House race, former Hill staffer John Lewis (D) and former Montana state Sen. Ryan Zinke (R) won their primaries to advance to the general election. Democrats are hopeful they can compete for the seat, which covers the entire state.
— This post was last updated at 3:30 a.m.