The top candidates for the Republican nomination are headed to the Values Voter Summit this weekend, an event that traditionally focuses on faith and social issues. Few Republicans name “moral values” as a top issue in the latest Washington Post-ABC News poll, but social issues linger as an important litmus test for candidates in the eyes of GOP voters.

Asked in an open-ended format about the top issue in their nomination vote, over half (51 percent) of Republicans and GOP-leaning independents cite the economy. Far below, 13 percent say the budget deficit or spending, 7 percent say ethics and corruption, and 4 percent each name taxes and health care. A scant 3 percent offer “morals” or “family values” as a top concern. Even among Republicans who first chose the economy as a top issue, 1 percent say moral issues ranked second.

Though it fails to reach “top issue” status, a June Post-ABC poll shows many Republican voters may outright disqualify a candidate with less conservative positions on social issues. In that poll, Republicans said by almost 5 to 1 that support for gay civil unions would make them less likely to support a candidate (50 less likely, 11 percent more), almost as bright a scarlet letter as having an extramarital affair (54 to 4 percent).

Pushing for a constitutional amendment against same-sex marriage, though, receives mixed reviews. In the new Post-ABC poll, Republicans (and GOP-leaning independents) say support for such an amendment makes them more likely to vote for a presidential candidate by a by a 38 to 27 percent margin. And while majorities of white evangelical Protestants and strong tea party-supporting Republicans see such an amendment as a positive attribute for a candidate, the political calculus in a general election setting is dicier.

More than four in 10 Americans (42 percent) say support for a constitutional amendment banning same-sex marriage makes them less likely to support a presidential candidate. A quarter say it makes them more likely to support a candidate, while a substantial 32 percent say it makes no difference at all.

Read the full poll results.

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