0 (in the United States) a state where the number of Democratic and Republican voters is about the same, meaning that it has an important influence on the result of the election of the United States president:
This was a key Midwestern battleground state that Democrats saw as central to the party's efforts to reclaim the White House.
We've always known results in battleground states will be extremely tight.
The incumbent is facing a challenge in the battleground states.
California is not considered a battleground state, but some ads may air in the Bay Area.
