94 % of the population is Roman Catholic, there obviously is no close second or third.
   
Christianity, Judaism and Baha'i.
Judaism, Christianity, and Islam (three of the world's top 20 religions) all began there.
The top three soccer players in spain are Cristiano Ronaldo, Messi and Falcao. :)
nadal,messi and ronaldo
Muslim, Christian, and Jewish, the Moors were very tolerant.
Spain is 94% Roman Catholic. All the other religions only total 6%.    
Muslims, Christians (who were all Catholics at this point) and Jews, in order of population numbers.
1. roman chatolic 2. calvinistic 3. lutheran
Top three is Spain, Italy Greece
Spain.
70% of Spain is Roman Catholic, 2% other religions,25% no religion. Roman Catholocism is a denomination of Christianity