I'll go for Underwood, even tho it looks like he's less conservative here than IRL.
He was generally a supporter of local/state self-government on issues like prohibition and suffrage, and often opposed labor regulations.
I'll give you prohibition (note that he still opposes it in this timeline). However, he certainly wasn't a state's rights guy on civil rights and strongly supported a number of labor and economic reforms such as the income tax, banning child labor, and the creation of the federal reserve. Naturally, he'd have to be moved slightly to the left by virtue the fact that he fits best with the Farmer-Labor party, but that is a natural consequence of the state of American politics within this timeline.
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