Warming up his midterm election talking points, President Obama warned in his weekly radio address today that Republicans will try to privatize Social Security if they win back majorities in Congress this November. The president said he would fight to stop the GOP, who would “gamble your Society Security on on Wall Street,” a strategy that could wipe out people’s retirement in a downturn. Obama’s remarks were coordinated with a campaign by Democratic leaders tied to the 75th anniversary of President Franklin D. Roosevelt’s signing of the Social Security Act. Democrats have new reason to defend the program this year with the nomination of more conservative Republican candidates for Congress. Plus, they can recall President George W. Bush’s attempt to privatize it in 2005, hitting home the idea that a GOP majority would mean a return to Bush-era policies. With baby boomers retiring, Social Security’s reserves will be exhausted by 2037, and payroll taxes will then cover only 75 percent of retirees’ benefits.