Catholics make up a third of the population in critical swing states like Wisconsin, Michigan, Ohio and Pennsylvania.
Gehring says if Ryan wanted to help Romney with the Catholic vote, he would stop reminding people his budget was based off of his understanding of Catholic teachings.
"Ryan wants to have this debate on Catholic terms and I am not sure why," Gehring says. "He has been told he is getting it wrong. Catholics are not buying what he is selling."
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