Although there were a presidential system and political parties, it was basically a one-party system where other parties could not participate competitively. The ruling party may have provided incentives for Mexican citizens, and this was only done to suppress further revolts. However, what was provided up to the 1980's were not enough and other political parties began building more support by offering the hopes of more equality as demanded. I would classify this case as economics leading democracy. Competition in the world today among countries is on the level of economic development.
Strong economies sit on top of the world as dictators, making decisions affecting everyone.
To be competitive here, the economy depends on its laborers. I believe that democracy determines economic growth. However, the demands on the economy make a democracy as the Mexican example shows. Under developed countries are so because their government leaders are unwilling to give up control to the masses as the developed countries have done.