In a volatile and heated campaign, the GOP chose Akin to take on McCaskill over former state treasurer Sarah Steelman and wealthy businessman John Brunner. Akin won 36 percent of the vote, with Brunner taking 30 percent and Steelman 29 percent.
Unlike in other recent key Republican Senate primaries, including races in Texas and Indiana, none of the three candidates were traditional establishment picks, and each had sought to lay claim to the mantle of small government outsider.
But in the final days of the race, they had sought to appeal to different splinters of the conservative electorate.
Akin received a late surge of support from evangelicals, impressed by his close ties to former Arkansas governor Mike Huckabee and his long-standing support for conservative social causes.
In a speech to supporters Tuesday night, Akin prominently thanked Huckabee for his efforts, just after offering gratitude to God.
“The choice is clear in November,” he said, according to prepared remarks. “The big-spending, budget-busting, job-killing liberal or the less spending, balanced budget, job-creating conservative?”
McCaskill appeared to be rooting for Akin as well. She ran ads clearly designed to boost his chances — criticizing him as the most conservative candidate in a backhanded attempt to appeal to a Republican electorate looking for the most right-leaning choice, an unusual strategy that could have boosted his numbers.
A race against Akin will let McCaskill highlight his long record in Congress, including support for earmarks and recent votes for the controversial Republican budget written by House Budget Committee Chairman Paul Ryan (Wis.).
Brunner, a first-time candidate who spent more than $7.5 million of his own money, positioned himself as a Mitt Romney-style job creator, basing his campaign on his years as head of successful health-care product manufacturer Vi-Jon.
Steelman received late support from former Alaska governor Sarah Palin, who has had the golden touch this year — every candidate she has endorsed has won his or her primary. Palin invested considerable energy in the race.
But the real question Tuesday was whether the identity of the Republican candidate would matter much to the outcome in November of a race that will test McCaskill’s folksy and tireless campaigning style.
National Republicans have long believed that she would be vulnerable to any challenger, after voting in favor of Democratic health-care reform and the economic stimulus plan. They think she took a hit as well when it was revealed in 2011 that she had not paid property taxes on a private plane. She later paid the taxes and sold the plane.