Margaret Cho, who was on DWTS this last season, has no bone to pick with Bristol Palin.  In fact, they became friends, Cho says:

I really like Bristol as a person. She’s warm and incredibly supportive, and I think that she looks beautiful out on the dance floor. It’s heartbreaking that people are so awful to her about her weight. I think she looks fantastic, and why does everybody think they have a right to comment on our bodies?

But Cho also says this:

Why did Bristol do Dancing with the Stars? I heard from someone who really should know (really should seriously know the dirt really really) that the only reason Bristol was on the show was because Sarah Palin forced her to do it. Sarah supposedly blames Bristol harshly and openly (in the circles that I heard it from) for not winning the election, and so she told Bristol she “owed” it to her to do DWTS so that “America would fall in love with her again” and make it possible for Sarah Palin to run in 2012 with America behind her all the way. Instead of being supposedly “handicapped” by the presence of her teen mom daughter, now Bristol is going to be an “asset” – a celebrity beloved for her dancing. I am sure the show wasn’t in on this (but who knows anything really).

It wouldn't surprise me.