Hillary Clinton's campaign-in-waiting is plucking talent from Ready for Hillary, a grassroots group formed to build support for her candidacy. (Photo by Win McNamee/Getty Images)

Hillary Rodham Clinton's hiring spree for her expected presidential campaign has plucked top Democratic campaign talent from Washington, New York and elsewhere in recent weeks, but not - until Wednesday - from the grassroots booster group Ready for Hillary.

The group's co-founder, Adam Parkhomenko, will become director of the Clinton campaign's grassroots engagement operation nationwide, two Democratic strategists said. The hiring of Parkhomenko and several other staffers was first reported by the New York Times.

The Ready for Hillary super PAC is expected to shut down once Clinton becomes an official candidate. The group will then make its extensive database of Clinton supporters available to the campaign, including coveted young voters wooed by the group's campus recruiting visits in an iconic Hillary bus.

Many Ready for Hillary staffers made little secret of their desire to join the real expected campaign. As top campaign jobs were filled by others in recent months, some were worried that Ready for Hillary staffers might get sidelined.

Ready for Hillary was ready for this moment long before Hillary Clinton was ready.

Parkhomenko and co-founder Allida Black hatched the idea for the group in January 2013, just as Clinton was leaving the State Department after four years as secretary of state. Clinton was considered a front-runner for president even then, but put off all questions about her political future.

Although the group eventually attracted high-level support from some longtime Clinton donors, it was first viewed with suspicion by some of Clinton's close confidantes. Clinton backers who did not welcome the group feared it interfered with Clinton's plan to lie low for awhile after the State Department, and could contribute to a sense that another run for the White House was inevitable.

Parkhomenko, who had worked for Clinton's failed 2008 campaign, positioned ready for Hillary as the repository of grassroots support for Clinton, with many backers giving symbolic gifts of $20.16. But its membership list showed it was also bolstered substantially by big donors.

Several other Ready for Hillary employees will follow Parkhomenko into the campaign, which will be headquartered in Brooklyn. Neisha Blandin, who directs grass-roots fund-raising for the super PAC, will play a similar role in the campaign, Democrats said.