A Democratic group backed by former President Barack Obama intends to pour millions of dollars into an eclectic array of elections in a dozen states, in an effort to block Republicans from single-handedly drawing congressional maps after 2020, officials leading the group said.
The National Democratic Redistricting Committee, formed last year under the leadership of Eric H. Holder Jr., the former attorney general, has settled on a strategy to contest a combination of governorships, legislative seats and more obscure state offices to chip away at Republicans’ sweeping control of the redistricting process.
Mr. Holder said in an interview that the group was chiefly determined to deny Republicans so-called trifectas in state governments — places where a single party controls the governorship and an entire legislature, as Republicans do in Ohio and Florida, among other critical battlegrounds.
The group’s list of high-priority states includes most of the critical states in presidential elections. Mr. Obama, who has made redistricting a focus of his attention since leaving office, plans to visit some of those states in 2018, and Mr. Holder reviewed his strategy with the former president in Washington on Monday, aides said.
States at the top of the just-finalized target list include traditional purple states like Michigan and Wisconsin, where Republicans can currently design maps without Democratic input, and others — including Colorado, Minnesota and Nevada — where Democrats have significant influence in government but must defend it in the 2018 elections.
“From my perspective, success is if you break a trifecta,” Mr. Holder said, adding: “I don’t think that in December of 2018, you measure success only by whether you have assumed control of a particular state.”
Because of the broad authority Republicans hold in many states, and the favorable maps many Republican lawmakers have drawn for themselves, Mr. Holder said his group would spend money wherever Republicans appear to be vulnerable. In Ohio, that will mean pursuing not only the governorship but also the offices of state auditor and secretary of state, both of which play a role in shaping congressional maps. In Wisconsin and Florida, Mr. Holder’s group will help Democrats compete for the governorship and the State Senate majority.
In North Carolina, where there is a Democratic governor, Roy Cooper, but Republicans have control of the legislature by vast margins, the redistricting committee hopes to shave seats off the current Republican supermajorities.
Mr. Holder said he would campaign aggressively himself in some of these races, beginning with an election for the Wisconsin Supreme Court this spring. Both he and Mr. Obama will focus heavily on mobilizing African-American voters, Mr. Holder said.
The strategy has the potential to inject a new volume of money, on the Democratic side, into typically low-profile elections. Mr. Holder said the group has raised more than $16 million out of a previously announced $30 million goal, but it has not disclosed how much cash it has on hand.
The tug of war over congressional maps has begun years before the 2020 census, which will collect the data used for reapportioning seats in Congress. Democrats have already sued to throw out congressional maps in several states and the United States Supreme Court is expected to consider a number of cases this year involving gerrymandered maps.
Republican leaders have long described control of the redistricting process as one of the party’s prized assets. Representative Steve Stivers of Ohio, the party’s campaign chairman in the House, said in an interview with Politico that “the congressional lines” were one of the Republicans’ great advantages in 2018.
But Republicans have also stressed that it is not gerrymandering alone that has kept them in power in the states. “Republicans won because they were better candidates with better visions for the people of their states,” said Matt Walter, president of the Republican State Leadership Committee, which spends millions in state legislative elections.
Mr. Walter has warned that Mr. Holder’s group represents a new force in state-level politics, and urged Republicans to prepare for better-funded Democratic efforts than in the past.
But absent Supreme Court intervention, Democrats may face an arduous, yearslong campaign to peel back Republicans’ overwhelming advantage in the states. A model for Democratic efforts, several strategists said, might come from Pennsylvania, where an all-Republican government implemented an elaborately gerrymandered map after the 2010 elections. Democrats later captured the governorship and the State Supreme Court, which recently voided the existing district lines and forced an icy standoff between Republican legislative leaders and Gov. Tom Wolf, a Democrat, over the creation of a new map.
Mr. Wolf said in an interview on Monday that he was optimistic Republican leaders would ultimately agree to redraw a “fair map” with his input. Mr. Wolf, who is running for re-election in 2018 in a race Mr. Holder’s group intends to target, said Pennsylvania could be a case study in bipartisan redistricting: “If I do it right, it is a model.”
But Mr. Wolf cautioned Democrats in other states not to twist electoral lines to their advantage and urged the few gerrymandered blue states to abandon their partisan maps. In states like Maryland and Illinois, Republicans have denounced Democrats for warping district maps even as Democrats denounce gerrymandering on the national level.
Beyond the traditional swing states, Mr. Holder said his group is eyeing some more daunting targets, including Georgia’s open governorship and the Texas Legislature, where Democrats hope to chip away at huge Republican majorities. And the group is monitoring a number of state-level ballot initiatives that could put anti-gerrymandering laws up for a vote this year.
“In some ways, that’s the best way to do it,” Mr. Holder said of referendums, “but state constitutions don’t allow that to happen in all 50 states.”
An earlier version of this article misstated the National Democratic Redistricting Committee’s plans for North Carolina. The group hopes to break Republican supermajorities in the State House and Senate. It does not hope to empower the governor to veto legislative maps, as the governor in North Carolina does not have that power.