Any immigration package in which current illegal immigrants are made eligible for Obamacare — in the form of either exchanges or Medicaid — could increase costs to the federal government by between $120 billion to $200 billion in its first decade, according to internal calculations by the Republican side of the Senate Budget Committee that were obtained exclusively by The Daily Caller.

GOP Senate Budget Committee staffers explained to TheDC that the estimates assume that the law’s provision capping total spending on exchange subsidies, which is set to begin in 2019, is enforced.

However, should the provision fall by the wayside, as some analysts believe it could, the staffers estimate the cost of Obamacare could increase between $210 billion to $300 billion over the next 10 years.

They add that if the capping provision is sustained, making millions of illegal immigrants eligible for Obamacare could also result in a benefit cut of approximately $1,100 annually for the average American receiving a subsidized benefit through the exchanges, which are now called “marketplaces” by the administration. (RELATED: Administration says “marketplaces” sounds better in Spanish)

Last March the minority side of the Senate Budget Committee estimated that Obamacare would increase unfunded obligations — or federal spending without a dedicated funding source — for federal health care programs by $17 trillion over 75 years, or from $65 trillion to $82 trillion.

Adding currently illegal immigrants, via a pathway to citizenship or other means, to Obamacare would further increase those unfunded obligations by another $2 trillion, based on their calculations.

To reach their conclusions, the staffers applied Congressional Budget Office estimates that 7 million illegal immigrants are without insurance, approximately 85 percent of whom have incomes low enough to qualify for the benefits — or less than 400 percent of the federal poverty line.

They further applied demographic data from the U.S. Census Current Population Survey to estimate that about half of the eligible illegal immigrants would be eligible for Medicaid, and the other half would be qualified for the subsidized exchange benefits.

Last week, TheDC reported the U.S. Citizenship and Immigration Services (USCIS) is updating its welcome materials for new immigrants to include information about the president’s signature health care law. (RELATED: Government gives immigrant materials a makeover)

The House Judiciary Committee is set to hold the first hearing on immigration for either chamber of Congress on Tuesday morning.

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