The need for a stronger central government
Federalists supported a government with federal or centralized power. The Constitution as written provided a stronger central government than the Articles of Confederation provided.
The Constitution provided for a central government with three branches of power to prevent any one branch from getting too much power. The Federalists supported the ratification of the Constitution as originally written. However, another group believed the Constitution needed to have a guarantee of protection of personal rights and protection of the states. Anti-Federalists refused to ratify until amendments were created protecting the people.