There have been many articles recently about how Rioja has become much more popular for the daily tipple of millions of Europeans and Americans around the world. Consumers are choosing cheaper bottles of wine to drink, usually sub $10, and can find great value with wines from Rioja, without comprising too much quality.
Rioja still is somewhat of a mixed bag, with many sub $10 wines not worth opening, but nowadays you can get Reserva and occasionally Gran Reserva wines in this price bracket, and that can make all the difference.
My favourite wines, from Ribera del Duero, still usually cost substantially more, but even this region, renowned for big, bold wines, is starting to turn out some reasonable wines under $20. I predict that this will be a trend that will continue, resulting in awareness of Ribera del Duero growing substantially over time.