When the Voting Rights Act (VRA) came before Congress this month, it enjoyed the vigorous backing of civil-rights advocates, social progressives and other familiar groups. The measure also attracted support from a surprising constituency: corporate chieftains. More than 10 top corporate executives urged members of Congress to renew the 1965 law protecting minority voters from discrimination at the polls. Among them were senior officials from AT&T, CBS, Coca-Cola, Comcast, Eli Lilly, Freddie Mac, Pepsi, Tyco, Verizon, Wal-Mart and the Walt Disney Co. Pfizer CEO Hank McKinnell also weighed in on behalf of the Business Roundtable, a group of 150 chief executives.