Washington ? Repealing President Barack Obama’s landmark health care overhaul would add billions to government red ink and leave millions without coverage, Congress’ nonpartisan budget referees said Thursday ahead of a politically charged vote in the House.

House Speaker John Boehner brushed off the Congressional Budget Office analysis as emboldened Republicans, now in the majority in the House, issued their own report arguing that Obama’s coverage expansion would cost jobs and increase budget deficits.

But Democrats seized on the CBO analysis, calling it a game changer in the battle for public opinion.

In a letter to Boehner, budget office director Douglas Elmendorf estimated repeal would increase the deficit by $230 billion from 2012 to 2021, the 10-year estimating period for budget projections. Moreover, Elmendorf said about 32 million more people would be uninsured in 2019 as a consequence.

But Boehner told reporters: “I do not believe that repealing the job-killing health care law will increase the deficit.”

The budget experts are “entitled to their opinion,” added Boehner, R-Ohio, saying that the analysts had to rely on information selectively supplied by Democrats who wrote the legislation. Not so, said the Democrats; adverse rulings by the budget office repeatedly forced them to go back and revise the bill as they were writing it.

The budget director’s verdict gave Democrats a new counterattack against Republicans elected on a promise to cut government debt. Until now, the main Democratic argument has been that repealing the law would eliminate benefits people are already receiving, from seniors facing high drug costs, to young adults who can stay on their parents’ coverage, to those in poor health who can now get insurance.

“We can’t afford to increase the deficit by nearly a quarter of a trillion dollars, especially with the very first substantive vote of the 112th Congress,” said Senate Finance Committee Chairman Max Baucus, D-Mont., one of the authors of the law.

“Republicans have to understand that health care isn’t going to be repealed,” said Senate Majority Leader Harry Reid, D-Nev. “They should get a new lease on life and talk about something else.” Reid has said he’ll block repeal in the Democratic-led Senate.

The White House issued a formal veto threat, saying the repeal bill “would explode the deficit, raise costs for the American people and businesses, deny an estimated 32 million people health insurance, and take us back to the days when insurers could deny, limit or drop coverage for any American.”

Republicans countered that even if it’s technically accurate that the health care law reduces deficits in the short run, a program that big is bound to bust the budget over the long term — and repealing it now will save money later.

The House has scheduled a procedural vote on repeal today, with final action next week.