Vice President Joe Biden told senior patrons at a restaurant today that there would be no changes to Social Security under an Obama-Biden Presidency, a guarantee that may force the top of the ticket to speak on this and other social insurance programs.

“Hey, by the way, let’s talk about Social Security,” Biden said after a diner at The Coffee Break Cafe in Stuart, VA expressed his relief that the Obama campaign wasn’t talking about changing the popular entitlement program.

“Number one, I guarantee you, flat guarantee you, there will be no changes in Social Security,” Biden said, per a pool report. “I flat guarantee you.”

The pool report noted that most of the patrons at the cafe toward whom Biden was directing his remarks were over the age of 60.

When the addition of Paul Ryan to the Republican ticket turned the Presidential race into a competing set of visions for social insurance programs, I thought it could go in two directions. Either the Obama-Biden ticket would straddle the divide and embrace a “bipartisan” deficit reduction plan which pokes at the sacred cows of liberals and conservatives, meaning that the “grand debate” of the campaign would be between a center-right and a far-right vision, leaving the entire idea that social insurance plans ought to be protected, if not expanded, off the table. Or, Obama and Biden would get forced into a corner and make promises on these programs that would conflict with their past attempts to reach a grand bargain that subjected the programs to cuts. Biden has basically done the latter here. It’s the kind of no-wiggle-room guarantee that could be useful after the election.

However. It’s only the Vice President talking. Someone needs to ask the President if he agrees. We’ve seen previously how Biden’s declarative statements have often gotten further out in front of where the Administration wanted to be, leading to either a walkback or, in the case of marriage equality, forcing Obama grudgingly in that direction. Maybe we’ll see the same dynamic here.

In addition, Biden’s declarative was made on Social Security. That’s not exactly the major issue in the campaign at the moment. After flirting with private accounts, Paul Ryan left Social Security untouched in this year’s budget. Mitt Romney has spoken favorably of raising the retirement age and means-testing benefits for well-off beneficiaries in the past, but he has not given a definitive answer on his plan for Social Security. The real fight has been about Medicare, and who cuts what and when. So in addition to pinning down Obama-Biden on Social Security, getting them defined on Medicare – and Medicaid, for that matter – would make sense as well.

A Presidential campaign based on deficit reduction and social insurance in a time of mass unemployment, a campaign aimed at Washington DC instead of Main Street and its struggles, is bad enough. But if Biden stumbles the President into drawing some bright lines on those programs, it could have a salutary effect.