Missouri's admission would give the South a majority in the Senate. Determined not to lose power, northerners opposed letting Missouri enter as a slave state. The argument lasted many months. Finally, Senator Henry Clay made a proposal. During the long debate, Maine had also applied for statehood. Clay suggested admitting Missouri as a slave state and Maine as a free state. His plan, called the Missouri Compromise, kept the number of slave and free states equal.Other Part of Missouri Compromise