The Sestak campaign has scheduled a news conference at 9:45 a.m. Tuesday at Progress Plaza in North Philadelphia.
Bloomberg spokesman Jason Post said the mayor supports Sestak as an independent thinker who has executive experience. Post says Bloomberg, an independent, has endorsed a handful of candidates whose values accord with his own. Sestak campaign officials say Bloomberg also cited Sestak's emphasis on tax breaks and small business lending initiatives.
Bloomberg began his third term as New York mayor in January. He was elected as a Republican but left the party halfway through his second term. Bloomberg briefly considered an independent run for president in 2008.