U.S. Senator Marco Rubio, a Florida Republican who may run for president in 2016, said Congress should “secure retirement for 21st century seniors” by raising the retirement age and letting many workers enroll in a federal savings plan.

“The future of retirement in America is very much in doubt,” Rubio said in a speech today at the National Press Club in Washington.

Rubio proposed allowing workers whose employers don’t offer retirement plans to enroll in the federal Thrift Savings Plan. The federal program, available to members of Congress, is a low- fee 401(k)-type system, the largest in the U.S. by assets, according to the Washington-based Investment Company Institute.

Almost half of Americans are “not at all confident” that they’ll save enough for a comfortable retirement, according to a March survey from Washington-based Employee Benefit Research Institute.

About 68 percent of U.S. workers had access to pensions or retirement savings plans as of March 2013, with 54 percent participating, according to the Bureau of Labor Statistics.

MyRA Plan

Rubio’s proposal mirrors President Barack Obama’s MyRA program, scheduled to start at the end of the year, allowing Americans to open individual retirement accounts that invest in a government bond fund. The so-called G Fund in the Thrift Savings Plan returned 1.89 percent in 2013, enough to outpace the 1.5 percent increase in the Consumer Price Index.

Rubio also proposed gradually increasing the retirement age for younger workers while protecting those currently 55 and older, and eliminating the 12.4 percent Social Security payroll tax for those who continue working at age 65 or older.

His plan would also “reduce the growth” of Social Security benefits for the wealthiest seniors, while “making the program even stronger for lower-income seniors.”

“This isn’t a cut,” Rubio said. “It’s simply a reduction in how fast the benefit will increase for wealthier retirees.”