KAMALA HARRIS, the presumptive Democratic nominee, is running a sped-up campaign. With less than four months until the election, she will announce her vice-presidential pick within days: new rules approved by the Democratic National Committee require her to pick one by August 7th. A running-mate can enhance a ticket—and, in theory, help bring support from voters that the candidate herself might not squarely appeal to—but rarely tips the scales. Ms Harris is reportedly vetting as many as a dozen people, but four are widely viewed as favourites. All are white men who have proved popular in swing states or, in one case, even in a firmly Republican one.