I don't think the writers of The Matrix meant anything political when the question was "the blue pill, or the red pill," but it makes a lovely allegory.
Unlike The Matrix, where taking the red pill dumps you from the artificial fantasy land where others control everything you see, hear and - for all practical purposes - think, in the real world the red pill (or the red party) is the evil group of mind-controllers. In the real world, the blue pill is the best bastion of sanity and freedom from oppression.
Just so we're clear: the Democrats are fucked up, too. It's a matter of degree. I'm finding it hard to locate any GOP member of the US Federal Congress who isn't a total sack of shit, without redeeming qualities. (Unlike the DNC, who are - today, anyway - only mostly sacks of shit, and many actually do have some redeeming qualities.)
It's a case of "lesser of two evils." The option is to dump the worse evil now, and continue pressing the standards upward, so that eventually the choice isn't "lesser of two evils," but "hey, these people are actually pretty good, let's keep them, and dump all the evil bastards once and for all!"