(CNN) - Hillary Clinton will get the endorsement of Pittsburgh Mayor Luke Ravenstahl at a campaign event Friday, sources close to the campaign confirmed.
The senator from New York will also get the backing of Allegheny County Executive Dan Onorato, the sources said.
Ravenstahl and Onorato are not superdelegates, but their endorsements add to Clinton's strong support among Democratic leaders in the state, where Clinton and Barack Obama will face their next contest on April 22.
Clinton also has the backing of Pennsylvania Gov. Ed Rendell, Philadelphia Mayor Mike Nutter, and the party's chairman in the state, T.J. Rooney.
Ravenstahl, 28, is the youngest mayor in Pittsburgh's history, according to the Pittsburgh Post-Gazette.