THE YEAR 2014 is only 66 days old, yet already Virginia has forfeited $330 million in federal funds — funds already paid to Uncle Sam by taxpayers — as a result of its delay in expanding Medi­caid to cover up to 400,000 lower-income and uninsured Virginians. With each passing day, the state leaves another $5 million in federal funds unclaimed. It has also passed up another $32 million so far this year in lost savings, as well as tax revenues that would be generated by the creation of some 20,000 health-care jobs.

Republicans in the House of Delegates, who have dug in their heels to block Medicaid expansion, do not dispute these figures, which were calculated by the Commonwealth Institute, an independent group that backs the expansion. They offer no real rebuttal to business groups that argue unlocking the federal funds would boost Virginia’s economy.

The state Senate, with Republican support, has backed an expansion plan that relies on market-based insurance. But House Republicans, led by Speaker William J. Howell (Stafford), are deaf to financial prudence and plain horse sense. For years, they blithely expanded the state’s Medicaid program on the basis of 50-50 cost sharing with the federal government. Yet now that the Obama administration has proposed an expansion that is a vastly better deal for the state — the feds would pick up 100 percent of the cost for three years, then 90 percent starting in 2021 — Mr. Howell and his colleagues refuse. In the process, they decline to make any proposal of their own that would cover hundreds of thousands of the state’s working poor.

The House Republican opposition to expansion is almost purely ideological; like most ideologies, it relies on faith more than facts. Since they have found it impossible to argue that the expansion is a bad deal for Virginia for now, GOP lawmakers insist that the feds, strapped by entitlement programs, will renege on their statutory commitment to cover 90 percent of the cost of expansion come 2021. That’s possible. But if Washington does renege, Virginia would have the option of dropping coverage and trimming its Medicaid rolls, as it has done in the past.

Bereft of coherent arguments, House Republicans have fallen back on publicity stunts. They have proposed dealing with Medicaid expansion in a special legislative session, thereby decoupling it from the state budget. But Mr. Howell and his colleagues have proposed no alternative to consider in a special session. And since Republicans have signaled their intentions by voting against the expansion, why should Democrats believe a special session would be anything but a charade?

Gov. Terry McAuliffe (D), having promised Virginia voters that he would push for expansion, is sticking to his guns, and rightly so. With an impasse at hand, the legislature will adjourn this weekend without having approved a budget. Both sides have dug in for a protracted fight, with the danger looming of a state government shutdown when the new fiscal year begins July 1. If that happens, Virginians should not soon forget the cause for which House Republicans will have brought the state to a standstill: a glorious crusade to deny health insurance to poor people and deny Virginians the benefit of the hard-earned taxes they have already paid.