Rather than seeking to block the new constitution, Congress simply forwarded it to each state to debate ratification. Morris's Republican faction, along with Federalist groups in other states, sought the ratification of the new federal Constitution. The Constitutionalists, who saw the new federal constitution as a threat to state sovereignty, joined with Anti-Federalists in other states in seeking to prevent the ratification of the Constitution. In elections held in October and November 1787, Morris's Federalist allies retained control of the state legislature and won a majority of the elections held to select delegates for the convention held to debate ratification of the Constitution. Due to a dispute with a business partner, Morris did not attend the ratification convention, which voted to ratify the Constitution in December 1787. By the end of 1788, the Constitution had been ratified by enough states to take effect. In September 1788, the Pennsylvania legislature elected Robert Morris and William Maclay, both of whom were aligned with the Federalists, as the state's first representatives in the United States Senate.