Marching for immigrant rights outside Independence Hall on Wednesday, about 100 placard-carrying demonstrators denounced Arizona's crackdown on illegal immigration and called on President Obama to honor his campaign pledge to bring about comprehensive reform.

The rally was also a launchpad for several Philadelphia area activists headed to Arizona to take part in protests this week.

Clergy, union members, students, and pro-immigrant groups came together Wednesday under banners with such slogans as "European Descendants for Immigrant Rights" and "Democracia Ahora," or "Democracy Now."

Carmen Marcet, a Peruvian immigrant who works in early childhood education in South Philadelphia, recalled a 2006 congressional bill that targeted illegal immigrants and the large-scale protests that helped to stop it.

"Now it's happening again and the people don't remember the story," she said, calling for another mobilization.

Estimates put the number of illegal immigrants in the United States from 10 million to 20 million.

Saying the federal government has been ineffective at controlling illegal immigration, Arizona lawmakers passed a law last month that requires local police to ask the immigration status of anyone they have stopped for any legitimate reason, provided they suspect the person is in the United States illegally.

About 17 states, including Pennsylvania, have proposed similar laws, according to Americans for Legal Immigration Reform, a North Carolina political action committee that favors tougher immigration controls.

In Pennsylvania, State Rep. Daryl Metcalfe (R., Butler) is the chief sponsor of a bill modeled on Arizona's Senate Bill 1070. State Sen. Daylin Leach (D., Montgomery) is the prime sponsor of a bill that would prevent Pennsylvania from implementing an Arizona-style law.

"President Obama needs to take control of this situation," Fabricio Rodriguez, a security guard, told the crowd. "It's not the role of Arizona Gov. Jan Breuer or Daryl Metcalfe."

Philadelphia Police Commissioner Charles H. Ramsey and other police chiefs from around the nation met Wednesday in Washington with Attorney General Eric Holder to tell him what they thought about the proper role of local police.

"Over the last 25 years we've worked hard to build relationships with minority communities" that are immigrant communities, Ramsey said after the meeting. "Enforcing immigration laws will cause us many problems in terms of those people feeling they can talk to us about crime issues and report crimes."

He said he worried about civil rights implications if police were to stop people based on the suspicion that they are undocumented.

"I don't know how you can do that without profiling," he said.

Speaking at the Philadelphia rally, Kent Matthies, a minister at the Unitarian Society of Germantown, told demonstrators America needs more immigrants, not fewer.

"I have a 17-month-old son," he said. "I do not want him to grow up in a homogeneous society. I want him to learn Spanish and Vietnamese."

The hour-long rally was briefly interrupted by Frank Gilanelli, a marketing manager from Moorestown. He said America is very hospitable to immigrants. All that Americans ask, he said, is that arrivals from abroad "please come through the front door."