In some aspects hockey is tied with football in Slovakia, but in the big picture football wins.
Even though there might be an even bigger lack of interest in the Slovak football league than in the hockey league, football is played at all levels. There are four things that are basically in every Slovak village - a church, a grocery store, a pub and a football pitch. The game exists in Slovakia on such a mass level that hockey could only dream of.
The only area where hockey used to win hands down was the national team, but that was in times when we had a great hockey NT and anot so good football NT. As an independent country the football team has only managed to make it to a top tourney once in 2010 (though they seem to be en route to a second one currently) despite the fact that back in times of Czechoslovakia, the Slovak part of the republic probably brought more to the success of Czechoslovak football at some points than it did bring to Czechoslovak hockey at any point of time - 17 out of 22 players on the team that won the 1976 Euro were Slovaks, on the hockey team Slovaks were in the minority every single time AFAIK.
Still, I'd say at least for this moment I'd still give the slight edge to the hockey NT over the football NT, but I think it's more due to the hype that for example surrounds the World Championship in Slovakia, even the hype that TSN creates for the WJC is small compared to what happens here around the Worlds - it's the two weeks in the year we could call ourselves the hockey republic, because you can't avoid hockey even if you'd want to.
Olympics are just as popular of course, but given the Slovak performance last year...
Anyway, comparing hockey to football on a global or even European picture makes little to no sense. You can compare hockey and football in Sweden, Russia, Czech republic or Slovakia, but not on a European level. Asides from Canada, US and Russia, hockey is a niche sport popular in a bunch of European countries with a population of 1-10 million. It might not even be crazy to say that even team handball is overally a more popular sport than hockey and it's a fact that the competition is higher in handball with more countries able to play on top level and more 2nd class countries who can on a good day beat the top teams than there ever were in hockey.