NBC News projects that Mitt Romney has won Arizona's 11 electoral votes.
The state has voted Democrat only once since 1972.
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The Prime Minister will make a direct pitch to Scottish unionists on her first trip of the election campaign north of the border.
Headteachers warn that the education system is facing a "real risk it will break".
Prince Harry will join rugby fans at Twickenham Stadium to cheer on the Army as they take on their Royal Navy rivals on Saturday.