Joseph R. Biden Jr. voted for the Defense of Marriage Act in 1996, blocking federal recognition of same-sex marriages. Two years earlier, he voted to cut off federal funds to schools that teach the acceptance of homosexuality.
In 1973, Mr. Biden, in an off-handed response to a question, wondered if homosexuals in the military or government were potential security risks.
But today, Mr. Biden, the presumptive Democratic nominee for president, has so completely identified himself with positions.