If Friday's campaign finance reports were ranked by sheer size, then we have a winner in American Cities, an independent expenditure political action committee funded by three Main Line stock traders who support state Sen. Anthony Hardy Williams for mayor.

American Cities reported raising $6,830,000 from Jan. 1 to Monday, according to a report filed today.  Of that, $6,651,000 -- or 97.4 percent -- came from Joel Greenberg, Jeff Yass and Arthur Dantchik, the founders of Susquehanna International Group.

That sort of spending was remarkable compared to the money raised by the six Democrats running for mayor in the May 19 primary and independent PACs supporting former City Councilman Jim Kenney.  By comparison, Building a Better PA Fund, which is running pro-Kenney television ads, raised just under $1.5 million in 2015.

American Cities spent $5.4 million in 2015 and had just under $1.5 million in the bank as of Monday.  The PAC has committed to spending $900,000 for television ads in the last week of the race.  The ads so far have been positive, talking about Williams' biography and record in office.

The SIG founders share Williams' support for school choice, including improving public schools, expanding charter schools and vouchers to allow public school money to pay private school tuition.  They spent about $5 million in 2010 when Williams ran for governor, finishing third in a four-way Democratic primary.

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