Conventional wisdom holds that landed elites oppose democratization. Landlords' political and economic influence may weaken with development, while commercial, financial and industrial elites grow stronger. Yet economic growth doesn't just alter the balance of forces; to the extent that landowners no longer need to control agricultural labor, it can actually change their political preferences. This occurs when landowners can substitute technology for labor. Mechanization dramatically increases agricultural productivity but also drastically reduces the demand for agricultural labor, which eliminates the need for labor-repressive policies. We explain how the adoption of labor-saving agricultural technology alters landowners' preferences for different regimes, so that the more mechanized the agricultural sector, the more likely is democracy to emerge and survive. This argument offers a parsimonious revision to Moore's thesis that applies to the ongoing real-world transformation of agriculture since Social Origins first appeared, and provides novel insight into the political consequences of what is the largest shift in human residential and occupational patterns in world history.