How hard will the GOP work to undo this?

Great news about the EPA's new rules to restrict the emission of mercury, which is a useful metal, but not one that anyone wants more of in the atmosphere and in the Earth's biological cycles.  Now, the articles indicate that compliance will cost money, which means that a regulation such as this might end up in the target reticule of the GOP enviro-bombers.   But here's the deal;  if the GOP runs against the EPA rules against mercury, which will reduce the levels of mercury in the environment, making fish safer to eat, allowing pregnant women to ingest more food without worrying as much about the neurological health of their fetuses (and fetuses are something that the GOP faithful are blood-sworn to protect), and even protecting sushi-eating celebrities like Jeremy Piven and Daphne Zuniga from mental and physical problems caused by too much mercury ingestion -- then the Democrats can run as if the GOP was in FAVOR of poisoning pregnant women, fetuses, and sushi-eating celebrities.  Well, maybe they should just mention the first two.  But I think the GOP would be pretty darned stupid to run in opposition to this necessary and welcome rule. 

Now, the GOP is pretty darned stupid, so I expect to see this mentioned prominently next year.