Forced Social Security coverage of state and local workers "would result in lower total retirement benefits and higher costs for taxpayers," Sen. Wayne Allard, R-Colo., wrote in a letter sent May 16 to Senate Finance Committee Chairman Charles Grassley, R-Iowa.

The Finance Committee has jurisdiction over Social Security legislation, which means if any reform bill is to become law, it must have the approval of the panel.

Allard's letter is similar to one sent to Grassley by 11 senators on March 2 and one sent to Grassley and Finance Committee Ranking Democrat Max Baucus of Montana by Sen. Barbara Boxer, D-Calif., on March 3.