HARRISBURG, Pa. (AP) — A federal court challenge to Pennsylvania's 17-year-old law banning the recognition of same-sex marriages took an important step toward a trial Friday when a judge rejected two different attempts to block the lawsuit.

U.S. District Judge John E. Jones III denied the motions to dismiss the lawsuit by Pennsylvania's secretaries of the departments of Health and Revenue and Bucks County's register of wills.

It is a strong sign the case is headed to trial and, potentially, the U.S. Supreme Court. In a note at the end of his 10-page decision, Jones set a Nov. 22 conference and advised lawyers in the case to be "fully prepared" to discuss the starting date of a trial.

Every northeastern state except Pennsylvania allows gay marriage. The lawsuit, filed July 9 by civil rights lawyers on behalf of a widow, 10 couples and one of the couples' two teenage daughters, was the first-known challenge to a 1996 Pennsylvania law that effectively bans same-sex marriage and recognition of such marriages from other states.

Since then, at least five more legal challenges to Pennsylvania's law have surfaced in state and federal courts, including one in which a Montgomery County official is defending his decision to issue 174 marriage licenses to same-sex couples.

In his ruling, Jones disagreed with what he called the defendants' predominant argument that his court lacks the power to hear the case. The defendants had cited a 1972 Supreme Court case from Minnesota that said a state law banning same-sex marriages did not violate the Constitution's equal protection and due process clauses.

However, Jones said that decision is weakened by the Supreme Court's evolving treatment of constitutional challenges based on sex or sexual identity in the past four decades.

"The jurisprudence of equal protection and substantive due process has undergone what can only be characterized as a sea change since 1972," Jones wrote.

A new Hawaii law makes it the 15th U.S. state to allow same-sex marriage, along with the District of Columbia. The governor of Illinois is expected to sign a bill into law next week legalizing same-sex marriage there.

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  • Connecticut

    Since November 12, 2008

  • Delaware

    Gay marriage law <a href="http://www.huffingtonpost.com/2013/05/07/delaware-gay-marriage-law-_n_3232771.html" target="_blank">enacted</a>, weddings to begin July 1.

  • Iowa

    Since April 3, 2009

  • Maine

    In 2012, Maine voted in favor of a ballot amendment to legalize gay marriage.

  • Maryland

    The gay marriage bill was signed into law by Gov. Martin O'Malley (D) on March 1, 2012. Opponents later gathered enough signatures to force the issue back onto the ballot in November 2012, but voters rejected the effort against gay marriage.

  • Massachusetts

    Since May 17, 2004

  • Minnesota

    Same-sex marriage bill signed into law in May. Gay marriages will begin in August.

  • New Hampshire

    Since January 1, 2010

  • New York

    Since July 24, 2011

  • Rhode Island

    Bill passed in May. Law takes effect on August 1, 2013.

  • Vermont

    Since September 1, 2009

  • Washington

    On February 13, 2012, Gov. Christine Gregoire (D) signed a law allowing same-sex marriage ceremonies to begin on June 7, 2012. The process was delayed by gay marriage opponents who gathered enough signatures to put the issue up to a state vote in November 2012. They voted to approve it on Election Day.

  • Washington D.C.

    Since March 9, 2010

  • California

    The state initially began conducting gay marriages on June 16, 2008. On November 5, 2008, however, California voters passed Proposition 8, which amended the state's constitution to declare marriage as only between a man and a woman. In 2013, the Supreme Court ruled against that law, and the state shortly thereafter began sanctioning same-sex nuptials.