LOL at the idea that the kind of people who've been supporting a deluded middle-aged woman desperately trying to be cool by rapping (essentially students doing it for a laugh, people who drink too much at home and weed-smoking idiots), would switch their support to someone who's basically doing musical theatre!
Seriously though, I don't think people really do switch allegiances and bother to vote for someone else in any kind-of numbers historically, so it's not something that actually makes a difference. Obviously some will re-vote, but the vast majority just melt away once their fave has gone I reckon. On forums you will see people saying otherwise, but the 'switched' support never seems to materialise in these competitions.