NEW : Newt Gingrich warns that liberal elitism threatens the United States . Mitt Romney gets a key endorsement from Michigan 's conservative governor . Rick Santorum appears to downplay his victory in August 's Michigan primary . The outcome of the Michigan primary will significantly impact the Republican primary .
NEW : Newt Gingrich warns that liberal elitism threatens the United States . Mitt Romney gets a key endorsement from Arizona 's conservative governor . Rick Santorum appears to downplay his chances in Tuesday 's Arizona primary . The outcome of the Michigan primary will significantly impact the Republican race .