Updated at 5:40 p.m. ET

Two liberal watchdog groups are challenging the strategy that four presidential hopefuls — Republicans Jeb Bush, Scott Walker and Rick Santorum and Democrat Martin O'Malley — are using to avoid legal contribution limits and disclosure requirements.

In complaints filed at the Federal Election Commission, the Campaign Legal Center and Democracy 21 say that while the four politicians all maintain that they're not even considering running for president, they all have crossed the legal line that defines a candidacy or a "testing the waters" phase in campaign finance law.

The complaints cite examples in federal regulations of conduct that turns a politician into a candidate. Three examples seem to describe what's gone on this winter and spring, when un-candidates have:

  • Referred to themselves as candidates. So far, it's always seemed to be by accident or reflex.
  • Demonstrated an intention to run for president over a "protracted period of time."
  • Raised more money than is needed to explore a candidacy, or launched "activities designed to amass" a campaign war chest. All four of the un-candidates have SuperPACs for which they raise unlimited contributions — a level of solicitation that would be forbidden if they threw their hats in the ring.

The complaints also cite regulations on the activities that define a "testing the waters" committee — the status the un-candidates are avoiding. Two stand out:

  • Spending money on polling to determine the candidate's "name recognition, favorability or relative support level."
  • Paying employees, consultants or vendors, and opening offices in states where primaries and caucuses will be held. In Iowa, where the first caucuses are scheduled for next February, Walker and O'Malley already have staff on the ground, while Bush and Santorum have Iowa consultants on retainer.

Lis Smith, spokeswoman for O'Malley's superPAC, O'PAC, said there was no merit to the complaint against the Democrat. She said, "We are confident that — whatever the case may be with the other potential candidates — that is what the FEC will find."
Walker is using the "issues-based" superPAC to talk about "his reform-minded principles in Wisconsin," said Kirsten Kukowski, spokeswoman for Walker's superPAC, Our American Revival. She didn't directly address the complaint but added, "If there are any announcements about his future he will do it in accordance with the law."

Spokesmen for the other un-candidates did not respond before deadline.

Paul Ryan, senior counsel to the Campaign Legal Center, said his group may also file complaints concerning other undeclared presidential hopefuls. So far, only Republican Sen. Ted Cruz, of Texas, has announced his candidacy.

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