Walker was a supporter of Common Core at first. Then changed his mind and called for repeal. He has since moderated that and is leaning more towards an “opt out” type of situation.
As far as Obamacare goes he has made few statements against it but the few he has made call for more of a repeal or replace type of situation.
Walker will focus on an issue mainly from the fiscal point of view. I’ve never heard him mention the unconstitutionality of the bill or death panels etc. He’ll speak about why he wouldn’t set up state exchanges in WI because he didn’t want the state to end up funding it. Instead of doing state exchanges here he expanded Medicade so that the poor can get coverage and others sent to the federal exchanges.
He believes there is no difference between the state and federal exchanges which caused a bit of a brouhaha from those that believed his statements threatened the case before the SC.
If you do a search on the internet using “Scott Walker Obamacare” you’ll run across a bunch of articles about it.