Republicans split between three choices in Missouri Senate primary

Republican voters in Missouri will decide Tuesday on a candidate to face first-term Sen. Claire McCaskill, an embattled Democrat whose seat could help the GOP take control of the Senate in November.

There is no clear front-runner in the three-way primary, but polls show each with an advantage over McCaskill, who is considered the most endangered Democratic senator facing reelection.

Tea party activists, emboldened by an upset victory in a Texas primary last week, see the Show Me State as the next arena to display the movement’s political might, but failed to coalesce around one candidate.

John Brunner, a wealthy executive who has poured $7 million of his personal fortune into his campaign, had been viewed as the most likely to win. But that was before Sarah Palin stormed into the state to endorse former state Treasurer Sarah Steelman and McCaskill weighed in with an ad branding Rep. Todd Akin as “Missouri’s true conservative.”

Steelman is also endorsed by the Tea Party Express, while FreedomWorks supports Brunner. Both are leading tea party groups that have been instrumental in helping elect conservative candidates.

McCaskill has run ads against each of her potential opponents, and her spot against Akin suggests she would prefer to face the six-term congressman, who has the backing of former Arkansas Gov. Mike Huckabee and Minnesota Rep. Michele Bachmann.

McCaskill seems to think Akin would have the hardest time winning support from moderates in November.

Regardless of the outcome, what is clear is that any of the three Republican candidates will enter the general election with a comfortable lead over a vulnerable incumbent in a state that has been tilting in the Republicans’ favor.

McCaskill won her seat in 2006 on the Democratic wave that gave the party control of both the House and Senate. She was one of six Democrats to defeat a Republican incumbent when she beat Sen. Jim Talent by just 46,000 votes.

Since then, the GOP has pulled off a string of victories, first denying Obama the state in 2008 and then defeating a household Democratic name in the 2010 Senate race. Republican Roy Blunt won that race by a margin of nearly 14 percentage points over Democrat Robin Carnahan.

Even though Obama lost Missouri by fewer than 4,000 votes in 2008, the state is barely considered a battleground for 2012. St. Louis lost its bid to host the Democrats’ convention, which will be in Charlotte, N.C., instead. And Obama has not campaigned in the state, to McCaskill’s dismay.

McCaskill was an early and enthusiastic supporter of the president. Her votes to support Obama’s policies on healthcare and the stimulus package sparked millions of dollars worth of attack ads against her.

She has been the subject of more than $15 million worth of attack ads, including $8 million spent by Republican-aligned nonprofit groups that aren’t required to reveal the names of their donors.

Democratic ad trackers expect that by November, the total spent on ads against McCaskill will be $33 million.

Follow Politics Now on Twitter

kim.geiger@latimes.com