In the wake of the Supreme Court's landmark ruling to free up corporate political spending, First Amendment advocates have scoffed at the notion that Citizens United v. Federal Election Commission will drastically redefine elections.

Like Justice Samuel Alito during President Obama's State of the Union address, free speech defenders have collectively shaken their heads and denied that much will change. Predictions of massive corporate spending and political deregulation are just so much hysteria and hyperbole, the ruling's champions suggest.

But another landmark legal challenge, argued before a federal appeals court just eight days after the Citizens United ruling, suggests that election laws will, indeed, never be the same. During oral arguments in SpeechNow.org v. Federal Election Commission, several D.C. Circuit court judges sharply questioned existing limits on political action committees, citing Citizens United as an argument for deregulation.

At issue is whether a pro-First Amendment advocacy group, SpeechNow.org, may run campaign ads without complying with the normal FEC limits on PACs. These require PACs -- political committees that expressly advocate the election or defeat of a candidate -- to accept donations no larger than $5,000 per election, and to file detailed disclosure reports.

SpeechNow.org's lawyers argue that, since the group plans to operate strictly independently from candidates, its activities pose no risk of corruption. The Citizens United ruling is relevant, they maintain, since it lifted the longstanding ban on direct campaign spending by corporations (and unions) as long as the expenditures are independent from, and not coordinated with, candidates or parties.

"That is simply the right of association, and people are entitled to associate with one another and be effective advocates," said Steve Simpson, a senior attorney with the Institute for Justice, which is representing SpeechNow.org. He added: "Our point is, an unincorporated association ought to be treated like a corporation. That's the bottom line."

In practical terms, a SpeechNow win would mean that as long as a politically active group acted independently, it could accept unlimited contributions from any source, and do so largely in secret. That's because FEC disclosure rules for so-called independent expenditures are minimal, requiring little detail on where the money came from.

Coupled with the recent Citizens United decision, reform advocates warn, a ruling in favor of SpeechNow.org would be a one-two punch knocking down election laws. That's because corporations and unions, thanks to Citizens United, are now free to underwrite such groups from their vast treasuries. Yet that money may never see the light of day if, as SpeechNow maintains, the PAC disclosure rules need not apply.

"You essentially would have blind spending," said Trevor Potter, general counsel of the Campaign Legal Center and former chairman of the FEC. "You would know that SpeechNow, whoever it is, has spent 'X' dollars against 'Y' candidate. You would have no idea where the money came from."

Potter did note that the judges hearing the case this month -- a nine-member en banc panel of a D.C. Circuit appeals court -- appeared inclined to support full disclosure. The lower court may side with SpeechNow in part but not in whole, he said. For example, the court might allow independent groups such as SpeechNow to receive unlimited contributions, but require them to comply fully with PAC disclosure rules.

Still, the SpeechNow v. FEC oral argument pointed up just how dramatically the Citizens United ruling has changed judicial thinking. A key and underreported aspect of the high court's ruling is its narrow view of what constitutes corruption. The Citizens United majority rejected the argument, upheld in previous Supreme Court cases, that corruption via "undue influence" or "access" justifies campaign finance limits.

One phrase, in particular, from the high court's ruling, has jolted campaign finance scholars: "The fact that speakers may have influence over or access to elected officials does not mean that these officials are corrupt." If the only constitutional rules are those that block blatant corruption in the form of a quid pro quo, say election lawyers, there may be few election rules the court is prepared to defend.

"The Supreme Court said explicitly in Citizens United that access is not corruption, and that's a major move," said Nathaniel Persily, a professor at Columbia Law School. "The Citizens United opinion is not simply about corporations. It erects a new philosophy to deal with campaign finance."

SpeechNow.org v. FEC is one of several pending cases that will soon test that philosophy. The Republican National Committee has challenged the soft money rules that ban political parties from accepting unlimited contributions from any source. And a fresh legal challenge to the ban on direct corporate contributions is expected soon.

In the near term, the Citizens United ruling may cause a ripple, not a revolution -- though that remains to be seen. But as the SpeechNow case points up, the ruling already has cast the existing campaign finance regime in a whole new light.

"We are headed to a much more deregulated system, where the question is: What is going to be allowed besides disclosure?" said Loyola Law School professor Richard L. Hasen. Referring to the high court's chief justice, he added: "The John Roberts wrecking crew is just getting started."