Your opinion is troublingly common here on FR. But if one cannot hold politically liberal positions and still be saved, then you undermine central tenets of Christianity (and certainly, Protestant Christianity): namely, that salvation is by faith alone, in Christ alone.
If we make it about thinking the right way on items that are not essential doctrine (the Trinity or substitutionary atonement, for example), then we make it about what we think and that comes awfully close to works-righteousness: what we do and think.
I was thinking more along the lines of supporting abortion, homosexuality, etc.
I do agree salvation is through faith alone. But will a Christian produce this kind of fruit??