While the new Washington Post/ABC poll has good news for Democrats, it contains some data that should cause them concern, according to Josh Marshall. Barack Obama leads John McCain in a general election matchup 51 percent to 44 percent, in the poll. Americans are also more concerned about McCain’s age than with Obama’s race or Hillary Clinton’s gender. But about a fifth of whites without a college education are uncomfortable with the idea of a black or female president, Marshall notes. Bob Barr’s announcement that he’ll run for president as a Libertarian might be more auspicious news for Democrats, Marshall adds. Barr, the former Republican congressman now running on an anti-war, small-government platform, could pull votes away from McCain in Western states where Obama is already poised to do well, the blogger writes.