A group of wealthy liberal donors who helped bankroll the Center for American Progress and other major advocacy groups on the left is developing a new big-money strategy that could boost state-level Democratic candidates and mobilize core party voters.

The plan, being crafted in private by a group of about 100 donors that includes billionaire hedge fund manager George Soros and San Francisco venture capitalist Rob McKay, seeks to give Democrats a stronger hand in the redrawing of district lines for state legislatures and the U.S. House.

The effort reflects a sense among many top donors on the left that Democrats missed opportunities in 2010 to shape the redistricting process and contain the tea party wave that helped propel Republican victories around the country.

Discussions about the new plan began last week in Chicago at a four-day conference of the Democracy Alliance, the invitation-only donor group founded in 2005 to build the kind of network of think tanks and activist groups that has long flourished on the right.

The focus on ground-level politics would mark a new emphasis for the Democracy Alliance, whose members have helped finance influential national liberal groups such as Media Matters for America, the media watchdog group; America Votes, which coordinates the efforts of allied interest groups; and Catalist, which provides voter data. The Center for American Progress, created during the George W. Bush years, has emerged as one of Washington’s powerhouse think tanks, serving as an intellectual engine for the liberal movement and the Obama White House.

Cecile Richards, president of Planned Parenthood, talks about Texas gubernatorial candidate Wendy Davis’s record and why it transcends her famous filibuster. (Jackie Kucinich/The Washington Post)

The alliance’s new president, Gara LaMarche, is pushing the group to take a “fresh look” at its overarching strategy as part of a regular three-year review of the organizations that it recommends for funding. The existing groups “have gotten to a certain scale that puts us in a better place,” he said. “The question we’re asking ourselves is, what are the capacities that need our resources now?”

Early ideas that have garnered support include directing more money to state-level donor groups, voting rights projects and organizations working to rally “the rising American electorate,” LaMarche said. “It’s becoming increasingly clear that mobilization and engagement of women, Latinos, African Americans and young people is the way to win elections,” he said, “and there’s a strong desire to invest more heavily in those communities.”

While maintaining a low public profile, the alliance plays an influential role as the left’s central money hub, attracting political donors interested in more than simply making campaign contributions. Last week’s meeting at the Ritz-Carlton in Chicago drewan array of Democratic powerbrokers eager to influence the donors’ thinking, including White House senior adviser Valerie Jarrett, AFL-CIO President Richard Trumka and Planned Parenthood President Cecile Richards.

Many of the group’s top contributors come from the party’s liberal wing. That was evident last week in the conference’s theme — “A New Progressive Era?” — and the focus by speakers such as New York Mayor Bill de Blasio on economic inequality.

The Democracy Alliance does not make contributions itself. Instead, donors who join the alliance, known as “partners,” are required to contribute at least $200,000 a year to groups it recommends. Among the partners are some of the country’s largest labor unions.

The system has pumped an estimated $500 million into an array of organizations on the left over the past nine years, according to the alliance. The group’s leaders had originally hoped the sums would be larger by now. By comparison, a network of politically active nonprofits backed by the Kochs and other conservative donors raised $400 million just in the 2012 elections.

But alliance membership has been ticking up recently, group officials said. Well-known Democratic patrons such as San Francisco hedge fund manager Tom Steyer and Houston trial lawyers Steve and Amber Mostyn joined in the past few years. Eleven new donors have come aboard in the last several months alone, officials said.

In Chicago, alliance partners pledged to give about $30 million this year to 20 liberal groups endorsed by the group, a slight boost over the amount raised for the same organizations last year.

A topline concern of many attendees: keeping Democratic control of the Senate. Speakers included Alison Lundergan Grimes, the Kentucky Democrat challenging Senate Minority Leader Mitch McConnell, as well as White House political director David Simas, who discussed how the president’s health-care legislation can be a boon to Democrats on the ballot.

“There’s a lot of anxiety about the midterms,” said McKay, the outgoing chairman, who said substantial investment this year will go to local and state minimum-wage campaigns that can help drive turnout for federal races.

But much of the conference, more than in past meetings, was dedicated to long-range strategy, attendees said. One participant, requesting anonymity to discuss private deliberations, described a sense in the group that “it is time to evaluate everything.”

That process could change where the money flows on the left. The alliance will determine in November which groups it will recommend for funding over the next three years.

The Chicago conclave — which featured a wine party in the Ritz-Carlton’s sky-view presidential suite and a private tour of the Art Institute of Chicago — drew accusations of hypocrisy from Republican Party officials, who noted that the wealthy donors met privately even as Senate Majority Leader Harry M. Reid (D-Nev.) was railing about the behind-the-scenes influence of the conservative patrons Charles and David Koch.

Democracy Alliance leaders rejected that, saying its members are seeking to reduce the influence of money on politics.

“There is a degree of irony in using the current system to change the system,” LaMarche said. “But the alternative is a kind of unilateral disarmament.”

Still, after long operating under the radar, the organization is considering ways to share more details about its workings. McKay said he is open to releasing information about what organizations the alliance recommends for funding. “I believe that we should be on a path to greater transparency about certain things,” LaMarche said, “and I aim to get there.”