This idea reminds me of an old pen-and-paper RPG from the 90's that never caught on called "Underground." Set in an alternate dystopian future, the only two political parties were the "Republicrats" and the "Plutocrats." Republicrats were the liberal party made of the remnants of both the Republican and Democratic parties who had any scruples. The Plutocrats were the rich, ruling class party who had abandoned all pretenses of caring about anything other than financial gain and power(comically founded by Ross Perot.) In general, it was understood that the Republicrats were a party of token opposition and the Plutocrats won every election.

In any case, if you're asking for an historical word, I'm afraid the closest I can come to someone who is socially progressive and believes in minimizing government expenses is libertarian, although it goes without saying that this is debatable.

However, the opposite, that is a staunch conservative who is politically populist, would be known in a certain time and place as a Dixiecrat.