(CNN) -- There was a time when the Republican Party was strictly for White Anglo Saxon Protestants. It was an alliance between Country Club Episcopalians and twice born followers of the Old Time Gospel, all firmly opposed to mass Catholic immigration from Europe. The nativism of the GOP drove Catholics into the welcoming arms of Al Smith, Jack Kennedy, Tip O'Neill and the Democratic Party. But this year's GOP front-runners are a Mormon and two Catholics -- Rick Santorum (a cradle of Italian descent) and Newt Gingrich (a convert). Roughly one-quarter of Republican primary voters are Catholic. Notable Catholic GOP leaders include John Boehner, Paul Ryan, Christine O'Donnell, Marco Rubio and Jeb Bush. Six out of nine justices of the Supreme Court are Catholics, and five of them are Republicans.
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Timothy Stanley: The Republican party was once dominated by Protestants
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He says Catholics and Catholic theology now play a key role in the GOP
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Stanley: Conservative Catholics have led the party's social issues conversation
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He says social issues play a key role in primaries, due to Catholic-evangelical alliance
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That certainly made the @placeholder an invaluable partner during the culture wars of the 1980s and 1990s.
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Despite the organization's reputation for being the political voice box of televangelists and peddlers of the apocalypse, by the mid '80s it drew a third of its funding from @placeholder donors.
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Santorum's political theology has thus moved him so sharply to the right that it's sometimes difficult to culturally identify him as a @placeholder.
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In a March 18 survey, less than half of @placeholder Catholics actually knew the candidate was himself a Catholic.
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In a March 18 survey, less than half of GOP @placeholder actually knew the candidate was himself a Catholic.
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In a March 18 survey, less than half of GOP Catholics actually knew the candidate was himself a @placeholder.
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And it is evangelical support that has elevated @placeholder to his current status in the race.