Alexander Cummings McWhorter Pennington, Sr. (July 2, 1810, Newark, New Jersey - January 25, 1867, New York City) was an American Whig Party / Opposition Party politician who represented in the United States House of Representatives from 1853-1857. Born in Newark, New Jersey, July 2, 1810, he attended the United States Military Academy, West Point, New York, from 1826 to 1828. He went on to study law, was admitted to the bar in 1833, and commenced practice in Newark. He was elected a member of the New Jersey General Assembly in 1837 and 1838. He served as alderman of Newark from 1837 to 1840.