MARKETS: Markets work pretty well for certain things, since they give people incentives to do things other people want. People are going to want material comforts, and it's a nifty system to force people to benefit others to get those things. Unfortunately, there are a billion ways for markets to go wrong, especially when capital accumulates among a small part of society. Letting markets run wild gives very bad real-life results, which is why you'll always get popular support for regulation and social programs.
CORRUPTION: Running against corruption is silly on a number of levels. No political party ever ran in favor of corruption. No political party is inherently immune to corruption, especially if it establishes a long-term majority. The only serious anti-corruption platform is one that changes the system in ways that make corruption difficult.
A party running against corrupt insiders isn't really winning people over to its ideology. That's part of the reason the GOP hasn't been able to accomplish much since 1994: they have been much more successful in political organization to idealogical persuasion. Congressional districts, the big racial shift, the K-Street project, etc. give them a pretty good structural advantage in winning elections, but it doesn't change the way people feel about Social Security, or stop the gradual acceptance of gay people.
The current GOP is more apt to corruption than the current Democratic Party, because a corporate donor base is easier to organize into a top-down distribution of power than a distributed donor base of net-hippies. On the same token, lefty socialist candidates are less apt to be corrupt than pro-business neoliberals.
FISCAL CONSERVATISM: Sort of a crock. Nobody vocally supports spending a lot of money on things they think won't work or don't matter. "We're spending too much" is intuitively appealing, but you can't really argue for the tax rate to be a certain percent of GDP without some serious discussion of what services the government should or shouldn't provide, and what the consequences will be.
IMPEACHMENT: Less likely than a ground war against Iran, barring live boy or dead girl.
MARSHALL WHITMAN: Has a weird consensus-fetish. "We need thoughtful solutions" presumes everyone agrees on the problems, and what would constitute a desireable result. Partisanship is useful. It's people who believe the same thing getting together and using the political process to influence government. I don't begrudge apathetic people wanting to drown out the noise. People who think politics are important and who make their living in it should know better, though.