This is kind of a pointless comparison with so much variation within the Protestant groups and nationally. In Minnesota the exit polls both showed Obama better amongst Protestants marginally and far better amongst mainline Protestants.
Ultimately though even though Harry once basically argued I should convert to Catholicism based on this on AIM the difference is that the Catholic church is all ran by one hierarchy while the Protestant ones aren't, so they can't be treated as a unified entity. And even if many people who identify as Catholic don't listen to the Vatican, plenty of people wouldn't be comfortable identifying as such as long as it's still running things. So renouncing Catholicism and converting to some Protestant church (like tons of people I know have) is hardly a "right wing act".
Minnesota =/= the United States. Are you familiar with the concept of aggregates?
Also, it is a right wing act if the Protestant church you're converting to is in the Southern Baptist Convention, the WELS, the Assemblies of God, or any number of non-denominational fundamentalist churches. And those are the Protestant churches that are growing the fastest.