WASHINGTON (AFP) - US Democratic presidential candidate John Kerry (news - web sites) promised to lift a ban on immigration to the United Stated by people with AIDS (news - web sites) and vowed to double US assistance to a worldwide campaign to combat the deadly and contagious disease. The new pledges, timed to coincide with the opening in Thailand of the six-day 15th International AIDS Conference, came as a new opinion poll showed the Massachusetts senator widening his lead over President George W. Bush (news - web sites). Kerry welcomed the upcoming conference and promised to work with US...