Final answer:
The key action by settlers in developing American constitutional democracy was their participation in constitutional conventions to draft state constitutions, leading to debates and decisions about government structure and extension of voting rights. This encouraged civic engagement and laid the groundwork for representative democracy.
Step-by-step explanation:
The key action on the settlers' part that was central to the development of American constitutional democracy was the widespread participation in the crafting of state constitutions, allowing citizens to debate and decide on the structure of their new governments and the extension of voting rights. This engagement directly influenced the principles on which the United States was founded.
Constitutional conventions in each state played a pivotal role in shaping the fledgling nation's approach to government, challenging the traditional elitist model that only certain individuals should have a say in governance. Through the creation of these state constitutions, civic engagement was encouraged, laying the groundwork for America's unique form of representative democracy. The debates and experiments in majority rule during the post-revolutionary era helped define how much democracy would be tolerated and who would wield political power, whether only landholders or a more broadened electorate.
In stark contrast to the conservative attitudes of the elite, the democrats, often coming from more modest backgrounds, pushed for giving common people more power in the political process. This shift towards embracing democratic principles was crystallized by landmark events such as New Jersey temporarily allowing single women to vote, and discussions over the governmental framework that sought to balance the interests between democrats and elitists, a struggle epitomized by the varying constitutions of Pennsylvania and Massachusetts.