The easiest way to challenge American political power at an individual level is to engage people with their own principles and ask them to be consistent in a way that political parties, inevitably, are not.
If a person is liberal, surely they must agree to be liberal toward every individual, and unafraid of any particular view; after all, this is the very foundation of freedom of speech. A consistent liberalism acknowledges this; it defends the right of free expression to every individual, including those with unpopular views. This is quite in contrast with the liberalism of the Democratic Party, which distinguishes itself by attacking the rural poor as too stupid to understand their own affairs in the event they are swayed by conservative appeals pointing out this fact!
Conversely, a conservative who is skeptical only in the face of governmental power, and happily ignores every other variety, is no conservative at all. Conservatism must be a skepticism toward all power, otherwise it is not a principle; anyone who argues that government is the only "coercive" authority under the sun should be invited to planet Earth for a stay, where examples abound. Similarly, arguments that "social order must be preserved," are easily undone by a principled conservatism which preferences certain social orders over others; few would argue that all things are justified simply because they exist.
Liberalism toward the individual, conservatism towards power; by another name, anarchism -- but nobody understands it by this name, and I find it a strong argument to say that most Americans never will. The relevant question for anyone engaged in social action is whether they want to speak persuasively to a clique of overeducated converts or to whomever they encounter in whatever context, usually on their terms.
Many popular principles can be broadened to their libertarian conclusions, obviating endless tutorials on "What is Libertarian Socialism?" -- which amounts to proselytizing the uninitiated with one hand, while sponsoring a kind of intolerance for those who "don't get it" with the other. It is too great a handicap to begin a course of social action anywhere most people are not.