I wouldn’t be too worried at this point. For a weak candidate like Romney to be even tied (or within margin) is pretty good. Once the fall breaks and a VP is added (along with continued economic stagnation), you will see him break away, I predict.
A lot of the approval for Obama is real soft at this point. His ‘strongly approve’ rating is in the mid 20s (Hardcore libs). And some of his approval is the Bradley effect as well - which will melt away inside the confines of the voting booth.
This poll probably reflects the growing impact of Obama’s “You didn’t build that!” idiocy.