For the title fight, I am sure that only three teams have a much greater chance while Bilbao has no chance to compete with Barcelona, Atletico Madrid and Real Madrid. We ignore Atletico Madrid as one of the teams that also has the capacity to win the title, although in terms of experience, maybe only Barcelona and Real Madrid are quite favored, but with the points they have collected so far, maybe everything can still happen beyond prediction.
There are still some matches left and we can see how consistent the three teams are in collecting points because if one of them has problems winning, the standings can change again and I think this is interesting because there is still no one who is quite a favorite.
Atletico Madrid are not too rich like Real Madrid and Barcelona but remember that in the last two decades, they are the only club that won La Liga title and they won two titles with Diego Simeone. It's very impressive if we know that last two decades are dominating years of Barcelona and Real Madrid with Messi and Ronaldo.
In this season, Atletico Madrid have very good performances and now they have very good rank, that opens their good chance of competing La Liga title. Athletic Bilbao will have to accept their fourth position as they are not good and experienced enough to win La Liga title. To win it, they must win not only Atletico Madrid but also two other strong competitors Real Madrid and Barcelona, it's impossible.
Bilbao is only adding flavor to the title race, and isn't among the title contenders, because they will finish on fourth position. I don't think that they can overtake any of the three clubs on top three positions. We shouldn't underestimate Atletico, because they might surprise us and win the title if Real Madrid and Barcelona make any slight mistake of inconsistency.