Sasse, who received the backing of top national conservatives like Sens. Ted Cruz (R-TX) and Mike Lee (R-UT) and former Alaska Gov. Sarah Palin, as well as powerful groups like the Club For Growth, focused his campaign message on repealing Obamacare and restoring the constitutional vision of the Founding Fathers.
The Associated Press called the race for Sasse. With 13 percent of precincts reporting, he was up 43 percent to Dinsdale's 26 percent.
Having won the primary, Sasse is the front-runner to win the general election in November. A recent poll showed Sasse 25 points ahead of Democrat Dave Domina, an attorney from Omaha who won the Democratic nomination.
Osborn began the race in the lead in part due to his high name recognition. Some polls showed his campaign faltered around the time it was revealed that Navy memo he provided to the media clearing his actions in a 2001 incident had actually been authored by a friend and not cleared through official channels.
Dinsdale made a late surge, utilizing his sizable wealth to finance a spurt of campaign ads. But he was harmed by prior donations to Democratic candidates and questions about his sister's role on the board of Planned Parenthood.
National Tea Party groups quickly declared victory as the race was called.
"Ben Sasse won this race because he never stopped fighting for conservative principles," said Matt Hoskins, executive director of the Senate Conservatives Fund, which spent $1.1 million on the race including coordinated contributions. "Ben Sasse will lead the fight to repeal Obamacare and enact reforms that give patients greater control over their own health care decisions. He will fight to stop wasteful taxpayer spending and balance the budget," Hoskins added.
“Ted Cruz, Rand Paul and Mike Lee? They’ve got reinforcements coming in January," said Jenny Beth Martin, the president of the Tea Party Patriots.
In his victory speech, however, Sasse sought to downplay the narrative of the race as a victory in a intra-Republican civil war, saying the Nebraskan voters he encountered on the campaign trail didn't care about that.
Sen. Jerry Moran (R-KS), the chairman of the National Republican Senatorial Committee, praised Sasse in a statement as well. "Ben is a problem solver who will be a conservative voice in our effort to repeal ObamaCare and bring much needed fiscal sanity to the Senate," Moran said.