Politics is ALWAYS a game of DEGREES. Nothing less, nothing more. John Quincy Adams changed parties from his dad's Federalists because he didn't think he could get elected with the name "Federalist." James Monroe, ostensibly opposed to "big government," signed off on dozens of pieces of legislation building roads, a national observatory, and so on. NO ONE IS PERFECT, and while I think that the campaign finance reform bill is certainly unconstitutional, so was prohibition---until they got an amendment after most states already had "dry" laws.
I've said before and will say again: in America the people get what they want. There will be no option of a "constitutional" party if 85% of the people view that as out of touch with reality. Instead, you work with what's here, winning when you can, losing when you must.