WASHINGTON - A group of Catholic theologians and leaders of Catholic organizations called on Republican presidential candidates to "stop perpetuating ugly racial stereotypes on the campaign trail."

The organization Faith in Public Life circulated the letter challenging fellow Catholics former Rep. Newt Gingrich and former Sen. Rick Santorum, both Republicans, to dial back from how they refer to the nation's first African-American president "with a title that evokes the past myth of 'welfare queens' and inflaming other racist caricatures." The group called the tactic "irresponsible, immoral and unworthy of political leaders."