A lot of people don't know what they are.....or what they believe for starters.
My immediate family growing up were quite conservative. Not necessarily Republicans, but definitely too conservative to be Democrats. My wife's family are staunch Democrats. As I've gotten to know them, I've discovered a very weird phenomenon with them. In general, they are fairly conservative, God-fearing, Baptist, SE KY people. When you ask them about Obama, they support him and cheer for him to the max......or any other Democratic name.....the Clintons, etc. However, when you ask them their opinion on varying topics, they (unknowingly) don't align with their party. Basically if you had them take a test on issues you would tend to find that every one of them would probably be identified as a Republican.....which is just blasphemous in their eyes. Then you ask them why they are Democrats.....and they reply, "My granddaddy was a Democrat, my daddy was a Democrat, my brothers are democrats, so I'm going to vote Democrat."
I've since educated my wife quite well and she has come to see that she's more or less an Independent.
But I've come to see this with a lot of people around me. People blindly following parties....without really questioning themselves why.
I've printed out platforms of JFK, GW Bush, Bill Clinton, Obama, etc.....removed their names....and asked people if they would vote for any of them. Even though they may identify with a party, they often can't tell who's platform they are. And often they vote for one that is clearly out of their party line.....then you tell them who the names are and they start saying that I changed the info......or they say, "Well, I meant to say that I'd vote for so-and-so."
People are sheep...