The primary opponents of the Constitution during its ratification process were the Anti-Federalists. The Anti-Federalists opposed the Constitution because they believed it would create a strong central government that could potentially infringe on individual liberties and the rights of the states. They favored stronger state governments and were concerned about the lack of a Bill of Rights in the original Constitution.
The Federalists, on the other hand, supported the Constitution and advocated for its ratification, arguing that a strong central government was necessary to maintain order and unity in the new nation.
The Whigs and Democratic-Republicans emerged later in American history and were not directly involved in the debates over the Constitution. The Whig Party, for example, was formed in the 1830s, while the Democratic-Republican Party was established in the early 1790s by Thomas Jefferson and others, primarily opposing the Federalists.