The Obama administration is “bending over backwards to give Obamacare to illegal immigrants,” Louisiana Republican Sen. David Vitter charged on Monday.

Sen. Vitter wrote to Centers for Medicare and Medicaid Services administrator Marilyn Tavenner on Monday with a hard line of questioning about the agency’s months-late effort to verify Obamacare sign-ups’ citizenship and immigration status.

“The Obama Administration is bending over backwards to give Obamacare to illegal immigrants — but won’t protect hard working American citizens who are losing their health care coverage,” Vitter said. “The Obama administration has been granting deadline extensions, making excuses, and turning a blind eye to falsified documents by illegal immigrants.” (RELATED: Report: Obamacare To Cancel Health Plans For 250,000 Virginians)

Obamacare’s first open enrollment period, originally scheduled to end March 31, was extended through April 15. But five months later, the Obama administration is still getting around to ensuring that those who have been using Obamacare coverage — and likely taxpayer subsidies — are actually eligible.

The administration says it has worked its way through 310,000 applicants with citizenship and immigration problems, and 115,000 of those customers will lose their health insurance on Sept. 30. If any of those applicants have been receiving taxpayer subsidies, it’s unclear whether the administration will actually be able to claw that funding back come tax season. (RELATED: Obama Admin Is Kicking 115K Off Obamacare Plans)

After determining who wasn’t eligible for Obamacare enrollment and kicking those customers off their plans, the administration offered yet another special enrollment period for those affected, in case they’re able to provide documents to prove their legal status after all.

Vitter charged that the repeated delays “further undermine” the supposed March 31, 2014 deadline for Obamacare coverage.

Citizenship and immigration is just one problem of many. Inconsistencies in Obamacare applications numbered in the millions during the first open enrollment period. CMS only began verifying income-related inconsistencies weeks ago, when it resolved the citizenship problems.

Now the administration is trying to resolve income problems with 363,000 applicants, who could lose their premium and cost-sharing subsidies Sept. 30 if it turns out they’re not eligible for taxpayer help. Vitter also pressed Tavenner to address the income verification process before the second open enrollment period.

“Last year was nothing short of a disaster and as a result the Administration continues to bend the rules for people who did not comply with the law in the first place, with an exorbitant cost to the U.S. taxpayer,” Vitter concluded.

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