Expanding full Social Security benefits to millions of citizens has bipartisan approval, but some senators are skeptical about making the move because of what it will do to the deficit.

The Social Security Fairness Act would repeal the Government Pension Offset and the Windfall Elimination Provision, which reduces Social Security benefits for those who receive pensions based on earnings from employment that are not subjected to the payroll tax and are not covered by Social Security. The bill passed in the House of Representatives 327-75 last month, and it will likely pass in the Senate despite warnings that doing so will expedite the end of the current program.