Updated

Less than a year after removing most limits on election spending by corporations and organized labor, the Supreme Court is signaling trouble for another campaign law that aims to curtail the political power of big money.

The court on Monday said it will consider dismantling Arizona's program that gives extra cash to publicly funded candidates who face privately funded rivals. Similar matching funds programs exist in a half-dozen other states and a handful of big cities.

The court probably will strike down the Arizona program, according to Richard L. Hasen, an election law specialist at Loyola Law School in Los Angeles. He said this will further imperil public financing of campaigns by taking away "one of the only tools" left to make public financing attractive to candidates.

The Arizona case is the fourth big campaign finance issue to come before the court since Chief Justice John Roberts and Justice Samuel Alito joined it five years ago and made it more likely to strike down federal and state regulations.

In January, the court reversed a centurylong trend to limit the political muscle of big business and unions, freeing them to spend money directly to sway elections for president and Congress.

On the federal level, Hasen predicted that no major contender for president will accept public financing in 2012 because candidates, including President Barack Obama in 2008, have been able to raise much more money privately.

Under the Arizona program, candidates who opt for public financing can get funds up to two times their base amount when they're outspent by privately funded rivals or targeted by independent group spending. The program was set up in response to public corruption scandals in the 1990s.

The high court already blocked the state in June from handing out the extra money in the recent election. The justices have agreed now to hear an appeal from opponents who say the public money chills free-speech rights of privately financed candidates and their contributors by inhibiting fundraising and spending.

The state should not "place its thumb on the scales in favor of the publicly financed candidate," said William Maurer, a lawyer for the conservative Institute for Justice who is representing some of the challengers at the high court.

Federal appeals courts have struck down similar programs in Connecticut and Florida since a high court ruling in 2008 voided the federal "millionaire's amendment." The amendment was intended to level the field for congressional candidates facing wealthy opponents who spend lots of their own money.

A federal judge in Arizona cited the Supreme Court decision in ruling against the Arizona Clean Elections program, but the 9th U.S. Circuit Court of Appeals in San Francisco found that the matching funds did not violate the First Amendment.

"The Arizona Clean Elections system, in effect for over a decade, helped move the state beyond egregious corruption and recurrent scandal," said Michael Waldman, executive director of New York University's Brennan Center for Justice. The Brennan Center is representing some defenders of the law.

Some form of matching public funds is in use in six other states — Maine, Nebraska, New Mexico, North Carolina, West Virginia and Wisconsin — the Brennan Center said.

Los Angeles and New York are among big cities that also provide public money to candidates.

A portion of the New York system could perhaps be a model of public financing efforts, even if the Supreme Court invalidates the Arizona program, said the Brennan Center's Susan Liss.

The city provides a 6-to-1 match for contributions up to $175 to candidates for citywide office, Liss said. Thus, a $175 contribution would bring $1,050 in public money, she said. Contributions over $175 are not matched.

Argument will be heard in the spring in two appeals joined together as one high court case. The appeals are Arizona Free Enterprise v. Bennett, 10-238, and McComish v. Bennett, 10-239.