"We could be having this conversation 15 years from now and talking about how President Obama, as a Democrat, was the president that started the path to killing Social Security"

◼ Payroll Tax Cut Could End Social Security - DAVID HOGBERG, INVESTOR'S BUSINESS DAILY

The 2-percentage-point reduction on employee wages originally was set to expire Dec. 31.

But House Republicans late Thursday agreed to adopt the Senate's two-month stopgap approach. They had pushed for a yearlong extension but they came under fire by President Obama and Democrats, who accused them of being willing to raise taxes on the middle class.

Few analysts doubt that the payroll tax eventually will be renewed beyond 2012. And that could be a slippery slope to ending Social Security.

"If the argument is that a 2% payroll tax cut helps job creation, then why not 4% or 6%?" Fichtner asked. "Why not get rid of the entire payroll tax if it is holding back job creation?"

But that would mean Social Security will no longer be funded by the payroll tax but by transfers from general revenues. That could change the perception, real or not, that Social Security is an earned retirement pension.

"It becomes a welfare program, and a lot of people will think that they're not paying into the system and want to cut back on Social Security," Fichtner said.