The Bush administration has sidelined a federal official who raised legal questions about whether John McCain, Republican senator, could raise private funds in his presidential bid. The White House late on Tuesday nominated Donald McGahn, who once served as an attorney for former majority leader Tom DeLay, to replace David Mason, a fellow Republican, as the chairman of the Federal Election Commission. Mr Mason raised hackles in some Republican circles early this year when, he questioned the legality of a McCain campaign decision to withdraw from the public financing system during the Republican primary.