It depends on how you define things.
As a whole the country has become more conservative over the last 30 years.
Hoover, Eisenhower, and Nixon would be considered liberal or even socialist in today's political landscape.
Neither political party would be considered liberal by historical or world measures. Most of history and the world would consider the US Democratic party to be a conservative party and the US Republican party to be extremely conservative. The Democratic party is only liberal compared to the Republican party.
to my knowledge a liberal could be a republican, but a liberal is more likely to follow democratic viewpoints. A conservative is more likely to follow republican viewpoints.
It also depends on geography. I liberal republican in texas would be a conservative democrat in New York, and vice versa.
I think is more democradic than anathing else... http://funadvice.com/r/bg4m3s7q571 This might help.
HECK NO. liberals are democrats in 99.9% of the case. Conservatives are the republicans