The fight between Democratic and Republican mining bills has shifted. Now, it's about how to tax a mining company. That argument took a strange twist this week when Americans for Tax Reform leader Grover Norquist entered the debate.

The Democratic bill says mining companies should be taxed on the amount of minerals taken out of the ground; it's called a "gross tonnage tax." The Republican bill would instead tax final profits. State Senator Dale Schultz says that's giving away natural resources.

"All kinds of accountants and businesspeople have raised their eyebrows over this and said companies have found ways to avoid paying taxes. It might be ten years, if ever, before this is profitable. "

But in Milwaukee yesterday, Governor Walker says no way to a gross tonnage tax.

"I'm not going to issue veto threats on legislation or amendments that haven't yet been offered, but I can tell you I can't support that and whether it's here or to the budget or anywhere else, I would do what is necessary to ensure that we don't have a new tax as part of the mining legislation."

Enter Grover Norquist. He sent emails to all Republican lawmakers telling them not to vote for the Democratic tax. Schultz got that email. "I was absolutely blown away. For a guy who has not exactly covered himself in glory with the fiscal cliff deal in Washington, it looks like he's looking for more fertile grounds in Wisconsin."

Schultz says this shows that the Wisconsin iron ore mining bill now has national interest. If passed here without the tonnage tax — which is also used in Minnesota and Michigan — it could become a national model.