WASHINGTON – California attorney and dedicated atheist Michael Newdow is making another run at “In God We Trust,” with a new Supreme Court petition challenging the national motto.

In an uphill battle, Newdow is asking the nine justices to review an appellate court’s rejection of his claim that the invocation of God on official currency violates the constitutional separation of church and state.

“Devout atheists are forced to choose between not using what is often the only available legal tender and committing what they consider blasphemy,” Newdow argued in his petition placed on the court’s docket Tuesday.

With his latest legal petition, Newdow now has multiple First Amendment arguments pending before the Supreme Court. Separately, he is also challenging the phrase “So help me God” in the presidential oath. Newdow said Wednesday that a third petition, challenging the Pledge of Allegiance, will soon arrive at the court.

Formal responses in the cases aren’t due until at least mid-February, and it could take several months before the justices consider the petitions in a closed-door conference. Nonetheless, Newdow concedes the odds are against him.

In 2004, the court heard Newdow’s challenge to the recitation of the Pledge of Allegiance in his daughter’s school, but the justices then ruled he lacked the legal standing to bring the case.

The four new justices appointed since 2004, including conservative Chief Justice John Roberts, have not measurably changed the ideological balance on the court.

The new petition seeks to overturn a March 2010 decision concerning “In God We Trust” by a three-judge panel of the 9th U.S. Circuit Court of Appeals.

“Even the most liberal court in America, the 9th Circuit, agreed with us that the national motto is clearly constitutional,” said Brad Dacus, president of the Sacramento, Calif.-based Pacific Justice Institute. “We are confident that the U.S. Supreme Court will do the right thing and end this frivolous lawsuit.”