The Mellman Group conducted a survey [pdf] of 600 likely voters in Missouri on the 2012 U.S. Senate race for Majority PAC from May 8-10, 2012. The margin of error is 4.0%. The poll memo was released yesterday:
McCaskill Continues To Lead The Missouri Senate Race Against All Comers
Despite being subjected to over $5 million dollars in negative attack ads from her Republican opponents, third party groups and Super PACs, our recent survey shows Senator Claire McCaskill leading all three of her potential Republican opponents in her bid for reelection. Indeed, her margin over the two opponents we examined in our last poll has actually increased since March 9th. Methodological failings render the results of other recent polls misleading.
Senator McCaskill has weathered a barrage of negative attacks and maintains a clear lead against all three of her potential GOP
opponents. McCaskill leads Sarah Steelman by 9 points (45%-36%) John Brunner by 8 points (46%-38%), and Todd Akin by 5 points (44%-39%) with 19%, 16% and 17% undecided, respectively.
Indeed, strong support for McCaskill nearly outpaces total support for her Republican rivals, with 36% supporting her strongly against Steelman, 35% supporting her strongly against Brunner, and 36% supporting her strongly against Akin. By contrast, barely a fifth of voters support Steelman (18%), Brunner (20%), or Akin (19%) strongly.
The poll memo includes a criticism of a sampling technique utilized in Missouri by other pollsters.
…In short, thanks to her overall lead, more intense support, and edge among independents and moderates, Senator McCaskill is poised to mount a winning reelection bid regardless of her eventual opponent.