WASHINGTON – Braddock Mayor John Fetterman ripped his rivals for the Democratic nomination in Pennsylvania's U.S. Senate race Wednesday, challenging their authenticity and casting himself as the only candidate who has genuinely dedicated himself to helping working class people.

In a wide-ranging interview with the Inquirer's editorial board, Fetterman – polling in third place in the four-way primary – painted front-runner Joe Sestak as being fixated on the military and assailed Katie McGinty as relying on poll-tested talking points. His comments were some of the most aggressive intra-party attacks of the race so far.

Asked about international trade deals, for example, Fetterman fired at his rivals: "They live in leafy, prosperous suburbs, and their communities have never been touched by free trade … they're just spouting off talking points."

He asked, "What in Katie McGinty's background or Joe Sestak's background gives any indication that they care about working class families or working class towns?"

While all the candidates have talked about the troubles facing the working class, Fetterman said he is the only one who has confronted the issue in office. He pointed to his tenure as mayor of a low-income borough ravaged by economic change and job losses as he tried to draw distinctions in a race in which the candidates have broadly agreed on the biggest debates of the moment.

"Only one candidate in this race has actually made the investment and made distinct policy improvements in areas that everyone is talking about and discussing in our race," Fetterman said,

McGinty has touted her own middle class background in Philadelphia – daughter of a police officer and restaurant hostess -- and has pledged to fight for manufacturing jobs and a higher minimum wage. She went on to be a top environmental aide for President Clinton and Gov. Rendell and served as Gov. Wolf's chief of staff.

"President Obama and Vice President Biden, who are two of the biggest champions for the working class, endorsed Katie because of her commitment to building an economy that works for all," McGinty spokeswoman Sabrina Singh wrote in response.

Sestak is a former admiral and congressman from Delaware County who has boasted of helping 18,000 constituents during his time in office, in part by keeping his offices open until 9 p.m. seven days a week.

"After congress, Joe taught at five Pennsylvania universities, but he also turned down pay as well as a seven figure lobbying job to work on education support for the poor in Philadelphia and disaster relief overseas and at home," said a campaign spokesman.

McGinty, Sestak, Fetterman and western Pennsylvania resident Joseph Vodvarka are competing for the Democratic nomination in the April 26 primary. The winner will challenge Sen. Pat Toomey (R., Pa.).

Sestak has led in public polling, with McGinty in second. Fetterman has lagged in fund-raising, but said he would launch television ads next week and presented himself as a candidate free of the typical political gloss.

"Our ads talk real people with real issues in real circumstances. I'm not in a roomful of actors pretending to be citizens," he said. The versions online so far feature Fetterman, the six-foot-eight, tattooed mayor, in his hometown, touring homes destroyed by drug addicts or driving to bridges in disrepair as the laments the amount of money flowing to elections, instead of infrastructure.

Poking at McGinty's diner tour of the state, he added, "I don't have some hokey diner tour where I have 12 people curated to ask questions that are in my wheelhouse."

And he blasted Sestak's persistent campaigning since losing the 2010 Senate race to Toomey, asking, "how does that help anybody except Joe Sestak?"

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