Jeff Horwich: Here at Marketplace we love playing “spot the veep” as much as anybody: Pawlenty, Jindal, Portman — all those names are bouncing around this week. But after the parlor games, how much difference does a vice president make when it comes to shaping economic policy?

From Washington, here’s some historical perspective from Elizabeth Wynne Johnson.

Elizabeth Wynne Johnson: It’s the office once famously described as “not worth a bucket of warm spit.” In the 19th century, vice presidents had little to do with policy, economic or otherwise.

That changed in the 20th century, but only to a point. According to Senate historian Donald Ritchie, Gerald Ford wooed Nelson Rockefeller by promising him a big say over domestic policy.

Donald Ritchie: Rockefeller was a big-government person. He was a Republican but he was in favor of stimulating the government, he was in favor of big spending projects. And Ford was a Midwestern conservative.

And Rockefeller never did get much of a say, after all. Ford’s chief of staff made sure of that. Historically, vice presidents affect policy most through relationships, says Prof. James Thurber of American University.

James Thurber: Many vice presidents are influential because they go to the Hill and get reactions and give feedback to the president. There’s nothing like a vice president that’s had experience on the Hill.

It certainly beats a bucket of warm anything.

I’m Elizabeth Wynne Johnson for Marketplace.