The majority of Jews are liberal, but a distinct minority are conservative. By the same token, the majority of Jews are secular, but a distinct minority are religious (and for some people, their political affiliation has become their religion). These facts are welcomed by some and considered unfortunate by others. Nevertheless, the most significant question is: do we generally judge each other by our actions or ideology? The answer to this question will determine whether we are rigid ideologues or just regular people with a certain political and religious bent. There are good and bad people of all mainstream political parties, and there are good and bad people of all denominations of Judaism. The moment we judge others solely on whether they have a (D) or (R) next to their name, or if they follow Jewish rituals the same way we do, we have allowed ideology to trump behavior.
If you happen to be engaged in a discussion with someone opposite you on the political or religious spectrum, limit your energy to the topic and never engage in personal attacks (which usually reveals a lack of sound arguments anyway). While all good people should be aggressively fighting objective evil, it's quite possible for two equally decent people to fight for different philosophies on the battlefield of ideas. There is nothing wrong with each of us having our own political opinions and ritual customs, as long as they don't lead us to abandon our most fundamental ethical concern: good interpersonal conduct.
An ugly manifestation of both politics and religion occurs when people start judging motives instead of actions. We can't come to the point where if my "team" does something, it's well-intentioned and good, and if your "team" does something, it's ill-intentioned and bad. The results of such an outlook are awful. And this leads to another important point: if we demean our ideological opponents, they will naturally want to defend themselves personally, but if we give them the benefit of the doubt that their intentions are just as pure as our own, they are forced to confront their views. So if you believe that a fellow Jew's political or religious ideas are out of whack, engage in a courteous discussion of the issues - not a demeaning back-and-forth of personal attacks. Otherwise, the debate is meaningless and it's best to avoid confrontation altogether.
Concerning political ideologues, there is an important lesson taught in Pirkei Avot (2:3) about those who run government: "Beware of rulers (i.e. politicians), for they befriend someone only for their own benefit; they act friendly when it benefits them, but they do not stand by someone in his time of need." If we place too much trust in politicians - even if we happen to agree with them on certain issues - we will ultimately be disappointed. As the famous saying goes, "power corrupts and absolute power corrupts absolutely." Politicians typically have only one thing in mind: getting re-elected. Therefore, most of them will do whatever it takes to be on the side of what is most popular (or what sounds good in theory, but ends up being disastrous in practice) just so that they can remain in power.
Concerning religious ideologues, there is an instructive story told of the Baal Shem Tov. He was once traveling on the road when he went into a wooden area to recite the afternoon prayer. His disciples were shocked to see him hitting his head against a tree, screaming and crying. Afterwards, they asked him what had happened. He explained that he had seen, with Divine Inspiration, that in the time before the Final Redemption, there would be a multitude of rabbis - and that they would be the ones who would impede the redemption. How is this possible? When rabbis stop following basic ethical guidelines and instead become technical ritualistic adherents. In other words, don't become like those who believe that everyone has to think and live the exact same way. Rise above such an inclination and allow for differences in thought and lifestyle, all while following the basic ethical precepts outlined by the Torah.
It's too bad that we can't determine whether someone is good or bad solely by how liberal or conservative they are, or by how religious or secular they are. It would make life so much easier. But people are much more complex than that. As a result, the only true measure of a person's goodness is overall behavior (something that is often very difficult to know). Vote how you wish and follow a denomination of Judaism that makes sense to you, but never assume that those who vote and observe Judaism differently have bad intentions. Human beings can judge actions, but motives are known to God alone.