One of the winning passages in Barack Obama’s speeches is his description of the Republicans flocking to his campaign rallies. “They whisper to me. They say: ‘Barack, I’m a Republican, but I support you.’ And I say ... ” – here Mr Obama usually lowers his voice to a stage whisper – “‘Thank you.’” The founding of Republicans for Obama this week by former congressman Jim Leach of Iowa, former senator Lincoln Chafee of Rhode Island and Rita Hauser, a former fundraiser for George W. Bush, seems merely to make official a phenomenon that is already widespread. “There is going to be a split in the Republican base on foreign policy,” Mr Chafee told reporters, “because the Bush-Cheney approach has been such a failure all over the world.”

Is this true? Mr Obama is making a big pitch to Republicans. He has spoken glowingly of Ronald Reagan, is friendly to religious voters and has invested heavily in advertising and staffing not just in the swing states of the Midwest but also in such Republican strongholds as Texas. Yet there are a number of myths about “Obamacans” (as Mr Obama calls them) or “Obamacons” (as pundits do). Their numbers are overestimated and their import is misunderstood.