Bill Clinton's 1992 campaign chief backs Obama's presidential bid

COLUMBUS, Ohio -- The man who served as national manager of former President Clinton's 1992 campaign plans to endorse Sen. Barack Obama, an aide to Obama said Wednesday.

Obama's campaign planned a 1 p.m. conference call Wednesday to announce the endorsement by David Wilhelm, who later became chairman of the Democratic National Committee, according to an aide who spoke on condition of anonymity because the announcement would be made public later in the day.

Wilhelm planned to tell reporters that Obama can build a coalition of Democrats, independents and Republicans needed to win the general election.

Wilhelm is a superdelegate who was previously uncommitted in the race. His endorsement helps Obama in the race for delegates, in which he pulled ahead after Tuesday's sweeps of primaries in Virginia, Maryland and the District of Columbia. Clinton remains considerably ahead in superdelegates, which are party officials, elected officials and others who can vote however they choose at the nominating convention.

If the race for pledged delegates based on outcomes in caucuses and primaries across the country remains tight, superdelegates could decide the nomination.

Obama leads the delegate race with 1,224 to 1,198 to Clinton, according to the latest count by The Associated Press.