Your theory is possible but I think the dems are not that nuanced. Their attacks tend to be more ham-handed. They see Rove as the reason they are losing elections (note, they are still in denial thinking that Rove is "tricking" the majority of the voting public) and if they can get rid of him, their political fortunes will change.
If they somehow were able to get Rove out (which will never happen), imagine their crushing suprise at their next defeat at the polls. Maybe, then, they would face the fact that the problem is in the mirror and not in some political genious boogeyman.