Democratic front-runner Biden has less campaign cash than top rivals

WASHINGTON/NEW YORK (Reuters) - Former U.S. Vice President Joe Biden had $9 million in his campaign bank account at the end of September, significantly less than his top rivals in the race for the Democratic presidential nomination, data released on Tuesday showed.While Biden leads most national public opinion polls, he has struggled to raise money and is relying heavily on wealthy donors who can write five-figure checks instead of smaller donations made via the internet.Biden raised $15.7 milli