For a few years now we’ve heard a rumor about a vodka drinking contest between Hillary Clinton and John McCain. The contest allegedly took place back in 2004 during a visit to the Estonian capital, Tallinn, by the two Senators. Normally, we wouldn’t be interested in a tawdry tale of senatorial boozing, but recently, some Clinton boosters boasted she won the contest. So the BBC’s Gabriel Gatehouse went to Tallinn to search for the truth.