Profiting from political schwag

(FORTUNE Small Business) -- Roving political-schwag seller Cameron Koepke expects a floor fight between John McCain and Mike Huckabee at the Republican convention, and he's been predicting a dead heat between Barack Obama and Hillary Clinton for quite some time.

Lugging his T-shirts and buttons around the primary states, Koepke correctly called the winners of the Iowa caucuses by using his sales and crowd enthusiasm as a gauge (he made no predictions for Super Tuesday). Obama, he says, is the strongest draw - although that hasn't always translated into the highest sales.

Koepke usually pockets about $1 in receipts for each voter at a rally, but Obama packs 'em in so tight that the average drops to 40 or 50 cents.

"With 1,000 people in a ballroom, there's one entrance and exit, and we can cover that with two people. But Obama's putting 10,000 in a building, and you can't see everybody," says Koepke. "But you have more volume, so it works out."