It was Congressman David Wilmot of Pennsylvania..
Ohio.
David Wilmot wasd a Congressman from Pennsylvania.
..banned slavery in all the new territories acquired from Mexico.
The Wilmot Proviso tried to prevent any of the new Western territories joining the USA as slave-states. Popular Sovereignty was the plan to allow each new state to vote on whether to be slave or free.
David Wilmot's home state is Pennsylvania. David was a US Senator and Congressman from Pennsylvania's 12th district during the 1800's.
He was a Republican Senator from Wisconsin.
He represented Massachusetts.
Barack Obama was a Senator from Illinois.
The Wilmot Proviso declared that none of the newly-acquired Mexican territories should become slave-states. The Abolitionists strongly supported this belief, and it drove the two sides further apart.
A senator's constituents are all the inhabitants of the state he has been elected as senator for. For example: Jim Webb is the senator of Virginia. Therefore, his constituents are the inhabitants of the state of Virginia.
The intent of the Wilmot Proviso was to not allow slavery in the new US territories. In 1846, US President Polk asked Congress to appropriate $2 million for expenses related to the war against Mexico. Congressman David Wilmot attached an amendment to this appropriations bill. Wilmot was a fellow party member of President Polk.