To me, the most respectable political movement nowadays in Spain would be
España 2000. They are a preferentialist (their slogan is "Spaniards First") and anti-immigration political party. They label themselves as "social-patriots". Actually, they are devoid of any ideological complexities. They exist just to give voice to those who are concerned about the immigration tsunami we are enduring in Spain and about the loss of our identity.
Currently they are strong in the area of Valencia, with to councillors. We'll see how they do in the next elections (spring 2008).