Complex sentence: In 1840 Smith played a leading part in the organization of the Liberty Party, and in 1848 and 1852 he was nominated for the Presidency by the remnant of this organization that had not been absorbed by the Free Soil Party.
Split into simpler sentences: In 1840 Smith played a leading part in the organization of the Liberty Party. In 1848 and 1852, Smith was nominated for the Presidency by the remnant of this organization that had not been absorbed by the Free Soil Party.