President Obama speaks at Master Lock

President Barack Obama is using the resurgence of U.S. manufacturing to make an economic case for his re-election, touring factory floors and promoting a made-in-America message that seemed to fit his political campaign like, as it turned out Wednesday, lock and key.

Most presidents like to surround themselves with proud workers at factories, but Obama has gone further by making the rebounding manufacturing a key plank of his election-year agenda, arguing that the increasingly service-oriented U.S. economy needs to make things in order to prosper in the long run. He opened a three-day political trip with a stop in Wisconsin, a state he won handily in 2008 but is expected to pose more difficulty for him this year.