How did the reformation spread democratic ideas?

First, Protestants emphasized being true to the Bible, and their own conscience which made people more willing to resist authority. Also, some persecuted groups such as Paritants sought freedom to worship in their own ways. Furthermore, Congregationalists insisted on the right of local Church group to control their own affairs. Finally, the leaders of Protestants churches were elected instead of being appointed by a central authority like the Pope which have prepare the way for democracy. Hope it help!