State Sen. Anthony Hardy Williams will announce his candidacy for the 2015 Democratic primary election this afternoon at 5:30 p.m. today at the Independence Visitor Center.

Williams spoke to PhillyClout before that event, describing himself as a candidate who can speak to voters from a "wide swath of perspectives" about problems they agree on, even if they are not united in how to solve them.

"You have to have someone who can talk to the neighborhoods and downtown, to share each others perspective," said Williams. "I think I've demonstrated those qualities over the years."

Williams was first elected to the state House in 1988 and then to the state Senate in 1998.  He was unopposed this year in the primary and general elections as he sought a new four-year term.  He does not have to resign from the Senate to run for mayor.

The Democratic field shifted Monday when City Controller Alan Butkovitz, an expected candidate, announced the he would not enter the race.  That prompted speculation that City Council President Darrell Clarke may run for mayor.

Butkovitz has said he would not run in Clarke runs.  Clarke declined to comment.

Williams said he is resisting being "defined" by other candidates in the race.

"I have a story to tell about me," he said. "I don't understand anyone who would run for the position based upon the perspective of who is in and who is out of the race."

Williams has the backing of U.S. Rep. Bob Brady, the city's Democratic Party chairman, but will face strong resistance from the local teachers union, likely with backing from the international union.  Williams ran for governor in 2010, pushing a school-choice platform that angers public school advocates.

Williams notes that he has supported increases in local public school education funding for years, including this year's push to tax cigarette sales in the city to help pay for schools.

His 2010 run for governor was largely funded by a small group of executives who run an international finance firm in Montgomery County.

This is expected to be the first mayor's race where SuperPACs and non-profits spend money to promote or attack candidates with no coordination with campaigns.

"We have diligently avoided talking about local government and specifically the mayor's race," Williams said on the financial firm executives.