WASHINGTON -- Former President Bill Clinton is coming to Philadelphia Thursday afternoon to raise money for Hillary Rodham Clinton's presidential campaign, according to two Pennsylvania Democratic sources.

The former president is due in Center City around mid-day in a state where much of the political establishment has lined up behind his wife's campaign. The sources spoke about the trip on the condition of anonymity, citing the sensitivity around the former's president's schedule.

Bill Clinton has kept a relatively low profile in the campaign so far, but in the past month has stepped up his fund-raising efforts, according to one of the sources. This is believed to be his first visit to Pennsylvania for the 2016 campaign.

Hillary Clinton came to Philadelphia in June for a fund-raiser hosted by Comcast executive and Democratic power broker David L. Cohen.

On the Republican side of the race, Florida Sen. Marco Rubio is scheduled to speak at an event hosted by the Chester County Republicans in King of Prussia on Thursday.

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