You have a great point.
The Democrat's favorite tactic against their political opponents is to dig up as much dirt as they can and then blow it all out of proportion and spin it till their opponent loses. The fact that they are going with this insignificant tax thing shows that they are scraping the bottom of the barrel...and they still have more than a year and a half to go.
Now, I'm not a Republican so I don't have a say in who they nominate, but it sure does look like Walker might be their best choice right now. I'm thinking Hillary would be toast if she has to run against him.