Based on Scott Walker's own actions and comments over the years – as in, “I was the original tea party in Wisconsin” – many voters and pundits regard Wisconsin's governor as a mainstream right-wing Republican, “mainstream” in the sense that the tea party has driven much of the party's modern ideology, to the chagrin of some of its putative national leaders.
However, now that he has a lengthening record as a state legislator, county executive and governor, it's becoming very apparent that Walker is fundamentally not driven by the often peculiar politics of his party's tea party wing. Rather, it seems to me, Walker represents the mainstream GOP's continuing fetish for statism.
That idea may raise eyebrows among observers with some knowledge of political science, since statism is often regarded as a government-centric, top-down philosophy -- one that Republicans, libertarians and other ideologues often seek to assign to the Democratic Party and anyone else to their left. But if you could describe Scott Walker in one word, I think it should be statist.