Republican presidential candidate Mitt Romney is airing campaign ads in Wisconsin, making a play to win the state last carried by a Republican in 1984.
Mr Romney hopes the ads, blaming Barack Obama for the federal deficit, can give him an edge in the state which is home to his running mate Paul Ryan and where recent polls have shown him even with the Democrat incumbent.
The former Massachusetts governor is also hoping to force Mr Obama to defend Wisconsin by spending additional campaign money there.
Mr Obama carried Wisconsin by 14% points in 2008 and has not aired ads there.
Independent groups backing Mr Romney and Mr Obama are running ads in the state.
Mr Romney, a native of Michigan, also hopes to compete there, which Democratic presidential candidates have carried since 1988.