forgive me for saying so, but this sounds awfully polly-anna-ish.
Rather, I believe that what is Poly-anna-ish is to expect that the political environments in which people live will somehow change directions radically.
You must understand that in most communities throughout the country there really is little chance of great turnover from one party to the other. Instead, entrenched organizations tend to control certain areas to a large degree, even to the point of making sure to draw district lines to effect the solidification of legislative or congressional seats wherever possible. Politicans HATE swing districts, afterall.
Consequently, one must bloom wherever they are planted. If you live in a Republican controlled district, your opportunity is to work within the Republican Party system. If you live in a heavily Democratic controlled area (where no Republican even gets elected for long) the potential which exists is to build up as best as possible the Democratic rule with politicians of your own purview who can enlighten the way with a culture of life.
What good does it do for someone to, say, run as a Democrat in a Republican district where he knows that his candidacy will be an utter failure? Or for a Republican to run in a Democratic area where he will be laughed at, unheard, not taken seriously, and get slaughtered at the polls? Would it not be better for such a person (who might make an excellent candidate and leader) to attempt getting into office as a member of the local ruling party? Would this not present that person with a better opportunity to actually gain a political foothold and make gains for doing good?
I think that holds a lot better potential and value in making real change than simply griping about how little a party does for the good and condemning them will ever effect.