Iowa's six electoral college votes have gone to Barack Obama, according to NBC News projections.
The President now leads Mitt Romney by 249 to 203, with Florida and Ohio yet to be called.
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Theresa May will attend a key EU summit on Thursday, just hours after her authority was diminished by a humiliating House of Commons defeat.
The best of the sunshine will be in the east.
The British territory will allow only domestic partnerships after senators approved the Domestic Partnership Act by an 8-3 vote.