Democrat Kamala Harris has raised $540 million in little more than a month since she began her race for U.S. president, with a surge of donations flowing in during the Democratic National Convention last week, her campaign said on Sunday. A memo released by Harris' campaign manager, Jen O'Malley Dillon, said the $540 million raised included $82 million that came in during convention week and is a sign of Democratic enthusiasm for her candidacy. "This is the most ever for any presidential...