The race was called for Ernst at roughly 10:53 PM ET.
The state senator had held a commanding lead over the rest of the primary field throughout the night. At 28 percent of precincts reporting when the race was called, Ernst had 54.3 percent support while the runner up, Sam Clovis, had 18.5 percent support.
Ernst will now face Rep. Bruce Braley (D-IA) in the general election.
Ernst received broad national attention for a series of ads she aired in the primary. One of those ads featured Ernst describing her experience castrating hogs and arguing that she would bring that skill to Washington to fight wasteful spending.