Are there exit poll data?
I guess it is strong D since 2000, like any other minorities. Even non-poor minorities, like Jews and Asians, are strong D.
The Atlantic did a good piece on this recently:
http://www.theatlantic.com/politics/archive/2015/12/republicans-muslim-vote-george-w-bush-donald-trump/419481/The gist of it is that since Bush2's early years, Republicans have lost virtually all of the Muslim vote. Obama's share of their vote, according to the article, was 89% in 2008. Based on the recent proposals and rhetoric from GOP candidates, they can probably expect to get even less support for now on.
http://www.cair.com/press-center/press-releases/12718-cair-exit-poll-shows-high-muslim-voter-turnout-in-midterm-elections.html
