Independent election monitors say under 46% of the electorate took part in Sunday's vote - the law requires at least 50% to make a ballot valid.

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The Government is asking returning officers on duty at this Thursday's London referendum to count as valid as many ballot papers as possible, even those where the voter's 'X' does not quite hit the spot.

BBC: 'X' marks the spot

In some states, you need about 750, 000 valid signatures to get on the ballot, says Richard Winger, editor of Ballot Access News.

BBC: US election: The third-party candidates

As you may know, Virginia requires 10, 000 valid signatures to get on the ballot for a statewide election, including 400 from each Congressional district.

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Imagine someone putting something on the ballot saying your wedding, your marriage is no longer valid.

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After the 30th ballot, only an absolute majority was needed for a valid election.

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