Heavens that website is God awful.. lol. O'malley before Sanders? Walker before Rubio and the such? Bush also has much shorter of a chance at the nomination than 50%.
Maybe 33%. but uh.. yea, quack source.
You don't understand how British betting odds work.
2/1 for Jeb Bush means that if you bet 1 pound on him and win, you get back your pound plus 2 pounds. Hence 2/1 would translate into something like 33.3%, but Paddy Power wants to make some money and therefore 2/1 means even a bit less, maybe 30%.
10/3 for Rubio means 1/(1+10/3)=3/13=23.1% or less, maybe 20% or a bit more.
7/2 for Walker means 1/(1+7/2)=2/9=22.2% or less, maybe 20% or a bit less.
You see, Paddy Power's odds are not too different from those on American markets.