HARRISBURG (AP) - Pennsylvania's Democratic candidates for U.S. Senate met for a 90-minute debate on Friday night, playing heavily to the liberal crowd watching them and forgoing any opportunity to try to attack each other, at least not directly or by name.

The event - between John Fetterman, Katie McGinty and Joe Sestak - came two months before Democrats pick a challenger to Republican incumbent Pat Toomey in the fall election and amid a sharp public debate over which president and which Senate should pick a successor to the late Supreme Court Justice Antonin Scalia.Speaking at the Keystone Progress Summit, which bills itself as Pennsylvania's largest annual gathering of progressive activists, the candidates each expressed support for labor unions, abortion rights, legislation that would protect women against wage discrimination and at least some level of support for universal, single-payer health care.Giving the audience of about 200 people what they wanted to hear, the candidates decried pharmaceutical industry lobbying muscle and stressed the need to battle climate change.McGinty repeatedly used her time to attack Toomey, Fetterman repeatedly raised his support for a $15 minimum wage and Sestak highlighted his choices of employment - nonprofits, not lobbying or consulting jobs - after leaving the military and Congress.The first question, perhaps inspired by the debate over the Supreme Court vacancy, sought answers on what kind of judicial nominees they as senators would recommend to the president. It began a night in which the corrosive influence of money and lobbying in politics was a persistent theme and, in particular, attacks on the Supreme Court's 2010 decision in favor of Citizens United versus the Federal Election Commission."Getting the poisonous influence of money out of our politics is the single most important thing we can do in this generation for future generations," said Fetterman, who is a small-town mayor from the Pittsburgh area. It has created an electoral playing field where "billionaires shop for candidates the way you and I would shop for a laptop computer."Sestak pointed to legislation he introduced as a congressman from suburban Philadelphia to create public financing of campaigns and said that taking money out of politics would "fix about 80 percent of the problems.""But there's more than that," Sestak said. "We need senators and congressmen who absolutely would not take a lobbying or consulting job as a revolving door, whether it's down there in Washington, D.C., as over 400 senators and congressmen have done, or whether it's in Harrisburg."The candidates, who are in line with President Barack Obama on his major initiatives, broke with him on at least one issue - the Trans-Pacific Partnership trade agreement that has divided Democrats in Congress and that is opposed by labor unions.On a question about single-payer health care, McGinty brought her answer around to Toomey, who opposes Obama's signature 2010 health care law."I agree, single payer would squeeze so much of the excessive cost out of our health care system," McGinty said. "But I tell you today, I'm focused on a Pat Toomey who not once, but probably 70 times now has tried to take away the fundamental right to health care."The candidates did not directly attack each other by name, and a mention of McGinty's strong establishment support - not necessarily a badge of honor with the crowd - didn't come up, although McGinty did mention some of her endorsements by labor unions.Still, during a question on climate change, Sestak pointed to his support for a halt to hydraulic fracturing back in 2010 when he ran for Senate, citing federal law that left it unregulated and some of its chemicals a secret.McGinty, who left her post as Pennsylvania's environmental protection secretary in 2008, at the dawn of Pennsylvania's natural gas drilling boom, does not support a moratorium on fracking, although both she and Sestak support federal regulation of it.Joe Vodvarka was not invited to the debate. The semi-retired spring manufacturing shop owner from the Pittsburgh area filed paperwork to make his third run for U.S. Senate.