Final answer:
John Locke contributed to American democracy by influencing the ideals of natural rights. Montesquieu's principle of separating powers greatly influenced the American government. Voltaire and Rousseau's ideas on freedom and popular sovereignty impacted the principles of American democracy.
Step-by-step explanation:
John Locke's contribution to American democracy was through his ideas on natural rights, which influenced the concepts of life, liberty, and property that are enshrined in the Declaration of Independence and the Constitution. Montesquieu's idea of separating powers within the government greatly influenced the structure and balance of power in the American system.
Voltaire's advocacy for freedom of speech and religious tolerance helped shape the principles of individual rights and freedom of expression in American democracy. Rousseau's concept of the general will of the people influenced the idea of popular sovereignty and the belief that government should be based on the consent of the governed.