According to the Rasmussen poll published August 9 [1] Jay Nixon is leading by 12%. 

Jay Nixon receives 51% voter support while Kenny Hulshof receives only 39% voter support.  Of those who have not yet made up their mind but are leaning in one direction or another, the results put Jay Nixon at 53% and Kenny Hulshof is at 42%. 

The poll also found that Matt Blunt had a 34% good or excellent rating for job performance and 39% rated Blunt’s job performance as poor.