In the jacksonian party system, congressional caucuses were replaced by for nominating presidential candidates. interest groups machine bosses party conventions ranking members

In the Jacksonian party system, congressional caucuses were replaced by party conventions for nominating presidential candidates. The Jacksonians are sometimes called the second party system; it is created around 1824 by Andrew Jackson who has his first run for the presidency. The party convention was created to replace the caucus.

bibliography and citations to credit the sources hope this you if not my deepest of apologize ^w^