PHILADELPHIA Former President Bill Clinton delivered a rousing speech Thursday to promote Marjorie Margolies' congressional campaign, assuring the audience that "I would be here even if her son weren't my son-in-law."

In a 25-minute stump speech at the Radisson Blu Warwick Hotel in Center City, Clinton praised Margolies not only for casting the deciding vote on his spending plan during her stint in Congress, but also for her work on gun control, student loans, and women's issues at home and abroad.

Clinton rejected critics' assertions that Margolies' only qualification is a vote from 1993.

"What she did 20 years ago is an ironclad assurance of what she'll do if you elect her to Congress," Clinton said, using the Margolies campaign buzzword, courage.

The ballroom was standing room only - there were no chairs - but only half-full, with an estimated 125 guests paying $1,000 apiece. Others had paid $5,000 a plate to have lunch with Clinton.

Margolies, one of four Democratic candidates to replace Rep. Allyson Y. Schwartz for the Montgomery County and Northeast Philadelphia seat, has retained front-runner status despite being behind in fund-raising through 2013 and declining to appear at several public debates.

Clinton's visit has been a centerpiece of Margolies' fund-raising strategy, and some of her opponents on Thursday attempted to blunt the "Bubba effect."

State Sen. Daylin Leach, a liberal favorite who has represented Montgomery County since 2003, released a video in which his 13-year-old daughter criticizes Margolies' campaign as "cling[ing] to the past."

An independent political action committee backing physician Valerie Arkoosh began a $210,390 radio campaign this week, with ads promoting Arkoosh scheduled to run on six stations 17 times a week through the May 20 primary, according to a buy sheet obtained by The Inquirer.

State Rep. Brendan Boyle, who has strong union support, is also running.

A dozen other politicians also spoke on Margolies' behalf Thursday, primarily touting her work on behalf of women and that 1993 budget vote.

"She has spent a lifetime fighting for women like me and the women in my family who, when we started out, didn't have the cash and connections to be in politics," said City Councilwoman Cindy Bass.

Clinton praised Margolies for the vote that sealed his budget and his presidential legacy, but said it was only one of her accomplishments as a legislator and as the leader of an international women's nonprofit.

He noted that Margolies voted for an education reform bill to allow income-based repayment of student loans that could save students $9 billion, and supported a ban on assault weapons despite strong opposition to gun control in Pennsylvania.

The Margolies campaign would not disclose Thursday how much money was raised.

But with Margolies leading the pack in expenditures - $17,000 a week on average in 2013, mostly for consultants and pollsters - her campaign coffers were less than half the size of her competitors' as of the last reporting period.

One thing Clinton and the other speakers did not discuss was Social Security, a hot-button issue that has fueled some of Margolies' harshest critics.

In the mid-1990s, Margolies sought to raise the retirement age and cut entitlement benefits for seniors.

In a debate Monday night, Margolies said she no longer supports those changes. But the liberal group Democracy for America said that as recently as December, Margolies had told it that "everything is on the table" to stabilize Social Security and Medicare.

"She's been flip-flopping on her stance," said Bev Hahn, who chairs the Montgomery County branch of the group and who led a small protest outside the Clinton fund-raiser Thursday.

Montgomery County Democracy for America has endorsed Leach, but Hahn said Margolies is the only candidate her group opposes.

Susan Comitalo, a teacher from Northeast Philadelphia, said she loved Clinton's messages about balanced budgeting (he said spending more than you take in is "like eating all the candy you want and never having to go to the dentist") and the rise in student-loan debt ("the government has not used this income-contingent loan repayment as much as they should have").

Comitalo and her mother, Loretta Trust, said they were supporting Margolies because of the 1993 vote. They said it showed Margolies was a tough woman.

"Women really need to step up and let America hear their voices instead of being oppressed by men all the time," Comitalo said.

"I don't think she'll back down," Trust said.