BOCA RATON, Fla. — Joe Biden may just be the perfect pitchman for the senior vote.

Seeing Medicare as a window to gain new support, President Barack Obama’s campaign dispatched the vice president to two sprawling Florida retirement communities Friday, hoping a white-haired 69-year-old running mate will be able to stir enthusiasm among seniors in Democrat-rich South Florida and tip the scales for the state’s 29 electoral votes.

“It makes sense,” says Charles Zeldon, a Nova Southeastern University expert on politics and voting. “He is one of them.”

Well, at least closer than Obama, a generation younger.

That may give Biden an edge in helping the president chip into Republican Mitt Romney’s lead among senior citizens, a key voting bloc not only in Florida but other battleground states such as Iowa and Ohio. The Democratic campaign doesn’t expect to win the majority of seniors, but hopes that lowering Romney’s totals could make the difference in close states.

Biden has spent much of the campaign trying to shore up support among white, working class voters, another group where he has a more natural connection than Obama. He’s aiming to use his same affable, plain-spoken style to persuade older voters to back Obama.

He stopped by a local deli later Friday, where he greeted a man who informed him he had once shaken the hand of President Franklin D. Roosevelt.

“I’m shaking a heckuva hand,” Biden announced. The man identified himself to reporters as Seymour Maiman, 85, of Ft. Lauderdale.

Biden hit all the expected notes before a crowd of about 850 at Century Village in Boca Raton, a popular campaign stop for Democrats. He spoke of Obama as a defender of popular entitlement programs like Medicare, and portrayed the plans of Mitt Romney and running mate Rep. Paul Ryan as harmful to seniors and their families.