Republican candidates looking for any conceivable advantage in their party’s nominating contest may welcome an endorsement from former president George W. Bush, but may be better off avoiding a nod from former rivals such as including Michele Bachmann and Herman Cain.

In a new Washington Post-Pew Research Center poll, most voters deny that endorsements from various politicians, newspapers or their religious leaders make much difference in their voting decisions, but some candidate testimonials are more valuable than others.

By a better than 2 to 1 margin, potential Republican primary voters say a Bush endorsement would make them more rather than less likely to vote for a presidential candidate. In all, 28 percent of registered Republicans and GOP-leaning independents say a candidate’s getting Bush’s support would make them more likely to vote for that person and 11 percent say less likely.

A Bush endorsement stands out as the most clearly positive from various Republican political figures. The only other GOP figure tested in the poll who offers a positive lift is the party’s 2008 vice presidential nominee Sarah Palin. Some 23 percent say her endorsement is a positive, 15 percent say it would be a negative.

An endorsement from John McCain is viewed more neutrally. The Arizona senator endorsed Mitt Romney last week. Herman Cain, the Georgia businessman who suspended his campaign for the presidency, also divides opinion down the middle. Cain has said he’ll announce his pick Jan. 19, just before the South Carolina primary. Seventeen percent say they’d be positively swayed to a candidate based on Cain’s recommendation; 15 percent say they’d be repelled by it.

Endorsements from Michele Bachmann and Donald Trump might actually hurt the intended beneficiary.

More fertile ground for Republicans would be endorsements of local worship leaders and governors. By a 22 to 6 percent margin, Republicans say they would be more likely to vote for a candidate endorsed by their priest or minister. Governors don’t wield quite the same power; 20 percent more likely and 14 percent less likely.

Local newspapers appear to be the least persuasive for Republicans. Only 13 percent say an endorsement from the local paper would make them more likely to vote for them and 13 percent say less likely.

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