barry cullen may enjoy a close horse race, but not close political ones. s worried that the great majority of voters in britain simply don't understand what's actually at stake. barry: if i was betting, i would say they stay in, but a very low-odds bet i think. evens. 50-50. >> barry is voting yes in the referendum, and hopes that in future he will still be able to enjoy his quick trips across the border to bet on the horses. >> with the polls looking really tight, i don't think i' be placing any bets on this referendum. what is clear is that britain decides to leave the eu, it could tear europe apart. which is why for our special program on the eu referendum in britain, i've come to another symbol of division: the thames, which separates north and south london. and i'm standing on the millennium bridge. it has some of the best views in the city. another spot though which straddles a divide is gibraltar: it's a remnant of the british empire and the southern tip of spain. because it is still british territory, people there are feeling very involved in this r