Until this month, Steven C. Roche was one of Mitt Romney’s most trusted advisers, helping the former Massachusetts governor raise tens of millions of dollars in his long quest for the White House.

Now Roche has jumped ship to Restore Our Future, a “super PAC” dedicated to helping Romney win the presidency by raising unlimited funds from wealthy donors and corporations.

The move, first reported by the Center for Public Integrity, illustrates the rise of yet another money-raising vehicle for the 2012 elections: “candidate super PACs,” which are emerging as de facto subsidiaries of the traditional presidential campaigns.

Super PACs are technically independent of candidates and parties, and are supposed to abide by Federal Election Commission rules prohibiting coordination with campaigns.

But many campaign-finance experts complain that the line is fast blurring into a distinction without a difference, in part because the FEC itself has loosened its regulations to allow much closer ties between campaigns and outside groups.

The trend has accelerated since the Supreme Court ruled in 2010 that corporations could spend unlimited amounts of money on elections, experts said.

“The candidate super PAC, which is new to 2012, is the most dangerous vehicle operating in American politics,” said Fred Wertheimer, president of Democracy 21, who has led the push for campaign-finance regulations since the scandals of the Nixon era. “It is a way, in essence, for candidates to raise and spend unlimited money from wealthy individuals, corporations and labor unions for the benefit of their campaign. That takes you very close to unlimited contribution limits.”

Each of the top GOP presidential candidates — Romney, Texas Gov. Rick Perry and Rep. Michele Bachmann (Minn.) — has one or more super PACs dedicated solely to assisting his or her White House bid. A Democratic super PAC, Priorities USA Action, is raising money to help President Obama in his reelection effort.

The groups are stacked with former aides and advisers such as Roche, raising questions among some critics about their purported independence. (A Restore Our Future spokeswoman declined to comment on Roche’s new role.)

The FEC has also issued several recent decisions that further loosen the standards that apply to super PACs. First, the agency decided that candidates are free to raise money for super PACs within the bounds of federal contribution limits; Romney has already participated in at least one Restore Our Future event.

Second, the FEC now says that super PACs can make donations directly to candidates without forming a separate organization, as long as the relevant funds are segregated, according to a legal settlement announced this week. That means a single group can both contribute money to a candidate’s campaign and spend unlimited funds to assist the same politician.

The end result of all these developments is that candidates in 2012 stand to benefit from a vast new fundraising apparatus with far fewer restrictions than those applying to the campaigns themselves. That could be particularly important in the Republican primaries, where pro-GOP super PACs are poised to swamp tiny states such as Iowa and New Hampshire with millions of dollars in advertising early next year.

“It’s always been the case that outside groups could help candidates, but now these super PACs are being run by their former top lieutenants and aides,” said Sheila Krumholz, executive director of the Center for Responsive Politics, which tracks campaign spending. “They are going to take a more central role, even in the primaries.”

Champions of looser regulations say the developments are good for democracy and free speech. In the latest FEC case, for example, a small super PAC called the National Defense PAC was successful in arguing that it should be able to contribute to candidates and make independent expenditures as long as the relevant bank accounts are separate.

“This is a major victory for grass-roots organizations that cannot afford to comply with burdensome regulations, or hire a lawyer if those regulations violate the Constitution,” said Allen Dickerson, legal director at the Center for Competitive Politics, which helped argue the case. “In acknowledging the unconstitutionality of its regulations, the FEC is making it easier for average Americans to engage in political speech.”

Brett Kappel, a campaign-finance lawyer at Arent Fox, said super PACs are poised to become “the de facto political parties” because of their broad ability to raise and spend money.

“These PACs will now be able to do what the candidates and parties can’t do,” Kappel said. “It’s moving the entire political system into super PACs.”

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