Brunner hit primary day as a shaky frontrunner for the GOP nomination. Polls showed Akin reducing a once double digit deficit to single digits and Steelman within striking distance.
McCaskill and the Democrats prefer to face Akin: Her campaign committee and the Democratic Senatorial Campaign Committee have run television ads calling him the race's "most conservative" candidate, a criticism, the real aim of which may have been to boost Akin with GOP primary voters.
Akin's fundraising lags far behind Brunner and polling shows he holds the smallest lead of the three versus McCaskill. His Washington job also makes it harder for him to run as an outsider than political-newcomer Brunner. And both men lack Steelman's ability to reduce McCaskill's advantage with women. In addition, Akin's support for earmarking gives the zealously anti-earmark McCaskill an easy contrast.
Missouri is a Republican-leaning state that President Obama is not contesting -- a step that McCaskill acknowledged reduces her ability to turn out Democrats. Any disclosures similar to last year's news that she billed taxpayers for flights on a charter plane she co-owned with her husband (she later reimbursed the Treasury Department) could also badly damage her brand as a good-government advocate. All that leaves her in an uphill fight against any Republican.
But McCaskill clearly hopes a two-way race offers her a chance to partly denationalize the contest and better employ personal advantages: Her communication abilities, electoral instincts and tenacity comprise a political skill set that even many Republicans strategists privately admit are superior to any possible opponents'. And with $3.4 million banked in her last Federal Election Commission report, she can outspend her opponents, although outside money may swamp that advantage.
McCaskill claimed her internal polling shows that she has maintained Democratic support.
"Now it's just a matter of independent voters getting informed about the positions of my opponent," she said. "That will be something that we will easily be able to do because they have doubled down on privatizing social security, privatizing Medicare, and getting rid of federal student loans.
"At the end of the day, do they want someone who's proud to be a moderate from the Missouri or do they want someone who wants to come out and join the tea party?" she asked.