The first party system ushered in the concept of modern political parties. During the late 1700s, American parties became an important, integrated part of the national government. Distinctly different from any other entity that existed before, parties allowed leaders to legitimately oppose government policies without opposing the concept of government itself. The leaders of the Democratic-Republicans, especially, learned how to become sensitive to the will of the people and how to respond to changing social conditions, something that the Federalists never fully grasped and which quickly brought about their demise. With a distinct national ideology, the Democratic-Republicans became an enduring organization through several administrations, learning how to rally support for their causes from like-minded leaders. Parties used the congressional caucus as a means of nominating candidates, and they recruited candidates for all offices, developing a party structure that would continue to be shaped into the nineteenth century.