The Missouri Senate race looks like a sheer toss up, in both the primary and general elections.

The Republican primary has always looked like a two way toss up between Todd Akin and Sarah Steelman, but now John Brunner deserves equal billing in that mix as well. All three candidates are within 5 points of each other with Steelman at 28%, Brunner at 25%, and Akin at 23%. Compared to PPP’s last poll in late January Brunner is up 7 points, Steelman is down 4, and Akin has remained right in place.

When the field for this race was first developing it looked like Steelman might play the role of a Tea Party candidate, but instead Brunner has turned out to be the top choice of ‘very conservative’ voters with 33% to 26% for Akin and just 20% for Steelman. Steelman’s strength is coming more from voters in the GOP center, as she leads Brunner by 21 points with moderates and by 8 with those identifying as only ‘somewhat conservative.’

The arc of this race is pretty unmistakable- Brunner’s the only candidate who’s really gained much support over the last year with Akin and Steelman remaining largely stagnant.

There’s no more clarity for the general election than there is for the primary. Claire McCaskill is basically tied with all three of her competitors, leading Brunner 46-44, dead even with Steelman at 44, and down 45-44 to Akin. Little has changed since our last poll when all three match ups came down at 43-43.

McCaskill’s approval spread is 40/50, numbers that don’t usually get a Senator reelected. But she’s benefiting from the current anonymity of the GOP field. Only 56% of voters are familiar with Steelman and that goes down to 43% for Brunner and 42% for Akin.The bad news for McCaskill is that the undecideds in these match ups are Republican leaning. Folks who haven’t made up their mind on McCaskill/Brunner voted for John McCain by a 61-20 margin in 2008. Folks who haven’t made up their mind on McCaskill/Steelman voted for McCain by a 46-34 spread. And the undecideds in McCaskill/Akin voted for McCain 49-30. Those numbers suggest the undecideds skew toward being Republicans who are just waiting to see who their nominee is, and once the fall field is set McCaskill could find herself in a dicier position.For now though this race is looking like about as much of a toss up as any other Senate contest in the country.