Earlier quoted context omitted.
Why do people love to act like both parties are the same? Is it just errant, broad pessimism? I understand wanting more options or not liking either available option but they're not the same. They don't have the same values, beliefs, principles, policies or experiences. They have many things in common, but they're not the same and it's not useless to talk about them and their perception in the polls.
If they weren't similar, then it would behoove them to become more so, lest the other party move to sway undecided voters. Plurality voting ensures that there are two major parties, and that they are as similar as possible without ceding ground to third parties.
1) Not vote 2) Start something like the Tea Party 3) Toss the incumbents out because they weren't extreme enough
This is happening on the left as well; we're becoming way more partisan as a country, and slowly but surely removing all the moderates from Congress.