By TOM RAUMAssociated Press WASHINGTON — Northwestern University athletes pressed their case for collective bargaining rights during meetings Wednesday with lawmakers, as a vote was scheduled for them to decide whether to authorize a union. The vote will be held April 25, according to Ramogi Huma, president of the College Athletes Players Association. During meetings on Capitol Hill, Huma and former Northwestern quarterback Kain Colter tried to drum up support just a week after a ruling that the athletes were employees and had the same rights to bargain collectively as other workers.