Republican presidential primary rivals Mitt Romney and Jon Huntsman are both Mormons whose ancestral roots run deep into the church’s pioneer history - intertwining, in fact, several generations back. Relatives of both men have served near the top of Mormonism’s global hierarchy. But in public remarks they have drawn strikingly different religious self-portraits. Romney is highly active and orthodox - he was a top local lay leader in Massachusetts for years, and he has embraced his church unequivocally: “I believe in my Mormon faith and endeavor to live by it,’’ he said in a major speech in 2007.