Michael Bloomberg to Endorse Hillary Clinton in DNC Speech

Bloomberg will speak at the convention Wednesday.

Longtime Bloomberg adviser Stu Loeser tells ABC News the former New York City mayor will speak Wednesday in Philadelphia and endorse the former secretary of state.

Another senior adviser to Bloomberg Howard Wolfson said in a statement: "As the nation's leading independent and a pragmatic business leader Mike (Bloomberg) has supported candidates from both sides of the aisle. This week in Philadelphia he will make a strong case that the clear choice in this election is Hillary Clinton."

The endorsement comes as a surprise. Bloomberg is a former Democrat, but was elected mayor of New York City as a Republican in 2001 and later became a Republican. Bloomberg was considering his own run for the presidency this cycle and has been critical of Trump during this campaign, but decided in March that mounting an independent run could help Trump's path to the White House. He has been especially critical of Trump's immigration and Muslim ban policies.