Complex sentence: New York state senator DeWitt Clinton moved for the adoption of the amendment in January 1802 and shortly thereafter won a vacant seat in the U.S. Senate, where he was instrumental in bringing the designation amendment to Congress.
Split into simpler sentences: New York state senator, DeWitt Clinton, moved for the adoption of the amendment in January 1802. Shortly thereafter, Clinton won a vacant seat in the U.S. Senate, where he was instrumental in bringing the designation amendment to Congress.