The Obama political operation that once buried Hillary Rodham Clinton’s White House ambitions is now rapidly converging around her possible 2016 presidential bid, conferring on Mrs. Clinton enormous early advantages in money, expertise and voter targeting techniques.
On Thursday, Priorities USA Action, a “super PAC” that played an important role in helping re-elect President Obama, announced that it was formally aligning itself with Mrs. Clinton and would begin raising money to fend off potential opponents for 2016.
The group — the largest Democratic super PAC in the country — also named new directors, appointments that will cement the group’s pro-Clinton tilt and thrust veterans of Mr. Obama’s political and fund-raising operation into the center of the post-Obama Democratic Party.
The move is perhaps the earliest start to big-dollar fund-raising in support of a nonincumbent presidential candidate, providing a fund-raising portal for wealthy Clinton supporters eager to help her White House prospects — and to the legions of others eager to ingratiate themselves with Mrs. Clinton and her inner circle.
Jim Messina, Mr. Obama’s campaign manager in 2012, who has forged close ties with many Democratic donors, will serve as co-chairman of the revamped super PAC and an affiliated nonprofit, along with Jennifer M. Granholm, the former Michigan governor, who is among the most persistent voices calling for Mrs. Clinton to enter the 2016 race.
Mr. Messina joins a growing list of Obama veterans aligning themselves with Mrs. Clinton: Jeremy Bird and Mitch Stewart, for example, who led Mr. Obama’s field efforts in 2012, are working closely with Ready for Hillary, a pro-Clinton super PAC that is focused on recruiting small donors and building lists of grass-roots supporters.
Priorities, by contrast, has begun seeking six- and seven-figure checks to power major advertising expenditures in support of Mrs. Clinton — including, if necessary, responses to attacks by Republicans and conservatives in advance of a formal campaign declaration. (Like all super PACs, the group would be barred from coordinating spending and strategy with Mrs. Clinton if she entered the presidential race.)
“I think the numbers clearly show that she’s the strongest presidential candidate on the Democratic side,” Mr. Messina said in an interview. “And Priorities is going to be there for her if she decides to run.”
Nick Merrill, a spokesman for Mrs. Clinton, said of Priorities: “While they are an independent entity acting on their own, their enthusiasm is flattering. In the end though, only she can make that very personal decision, and as she has said, she won’t be doing so anytime soon.”
Mr. Messina is now the highest-profile member of Mr. Obama’s inner circle to openly back Mrs. Clinton for president, a move that can only fuel perceptions that Mrs. Clinton’s potential candidacy has the tacit endorsement of Mr. Obama himself.
Donors and others involved with Priorities said that they would look to far surpass the $67 million that Priorities spent on attack ads against Mitt Romney during the 2012 election. Those ads — including the “coffin ad,” featuring workers laid off from a plant acquired by Bain Capital, Mr. Romney’s former firm — helped define Mr. Romney early in the campaign, a blueprint the group hopes to use on Mrs. Clinton’s prospective Republican opponents.
Steve Mostyn, a prominent Houston trial lawyer and Democratic donor who, with his wife, Amber, was among the earliest major donors to Priorities in 2012, said he believed that liberal donors would come out in force if Mrs. Clinton enters the race.
“Amber and I are both excited about the prospects of being part of the super PAC for Hillary if she decides to run,” Mr. Mostyn said. “The first time was kind of a leap of faith for us — it was back when no one was giving Priorities money. I think it’ll be easier with Hillary.”
Mr. Messina said he would focus on importing to Priorities some of the advances in television microtargeting developed by the Obama campaign in 2012, which allowed it to achieve unusual precision and cost-efficiency in finding and reaching voters, out-hustling big-spending groups on the right.
“Priorities did not have that ability last time, because we were on the other side of the wall inventing it,” Mr. Messina said.
Priorities’ long-awaited restart has drawn intense scrutiny in recent months, with press reports detailing the group’s courtship of Mr. Messina and of Clinton luminaries like John D. Podesta, a White House chief of staff under President Bill Clinton who is now a counselor to President Obama.
Mr. Messina declined to say whether he had discussed his new role with Mr. Obama or with Vice President Joseph R. Biden Jr., another potential 2016 candidate, and it remains unclear whether the group would intervene in a primary campaign should Mrs. Clinton face other contenders for the Democratic nomination.
Mr. Messina will join other Obama and Clinton veterans at the group, including Buffy Wicks, a former Obama field director now serving as Priorities’ executive director; Jonathan Mantz, who was finance director for Mrs. Clinton’s last presidential campaign; and Peter Kauffmann, a press secretary for Mrs. Clinton’s first Senate campaign.
The announcement cements a broader takeover by Clinton allies of the Democratic Party’s growing outside-spending infrastructure.
Priorities USA expects to coordinate closely with other groups involved in preparing for a Clinton bid, representatives of which will now sit on its board. They include David Brock, who is leading Correct the Record, a rapid-response squad dedicated to fending off attacks on Mrs. Clinton; Allida Black, a co-founder of Ready for Hillary; and Maria Echaveste, a former White House aide to Mr. Clinton who is now a fellow at the Center for American Progress, the liberal research group stocked with ex-Clinton aides.
The new board will also include Stephanie Schriock, the president of Emily’s List, which works to elect women who support abortion rights. She is considered among the contenders to manage Mrs. Clinton’s presidential campaign should she run.
“The Democrats are all cooperating, and the donors like it when they cooperate,” Mr. Mostyn said.
Mr. Messina will remain chairman of Organizing for Action, the nonprofit advocacy group that grew out of Mr. Obama’s re-election campaign and raised $26 million last year to advance Mr. Obama’s agenda on the environment, health care and gun regulation. The group shares several major donors with Priorities USA, including the New York philanthropist Amy Goldman Fowler; Barbara Stiefel, a Florida fund-raiser; and Fred Eychaner, a Chicago media executive.
But Mr. Messina said he did not believe that the Obama group and Priorities would be competing for the same dollars, since Organizing for Action takes in most of its revenue from Mr. Obama’s army of small donors.
“What I think Priorities is going to do better than anyone else is continue our data advantage and be on the offense,” Mr. Messina said. “Whoever runs for president.”