I’ve had an amusing stroll through the rightwing neighborhoods of the online Shtetl, where the bilious hatred for the president mixes with the humorous conviction that he secretly hates Israel, and I would like to propose a bet for anyone who wants it. If Obama wins less than, oh, 70 percent of the American Jewish vote in 2012, I buy you dinner at Sammy’s Roumanian. (He won 78 percent of it in 2008.) If he wins that or more, you buy me dinner there. Let’s see who has the courage of his or her convictions.