Gibson became involved in politics as a member of the Whig Party with strong anti-slavery views. During the U.S. Presidential campaign of 1844, he gave stump speeches for Henry Clay due to the Whig Party's platform that opposed admitting Texas into the Union because it was a slave state. In the U.S. Presidential campaign of 1848, Gibson supported Whig candidate, "Rough and Ready" General Zachary Taylor. However, he was concerned about the Whig Party's lack of opposition to the abolition of slavery and personally visited Henry Clay at his home in Ashland, Kentucky in 1848 to discuss this issue. He lost as a Whig candidate for Ohio Attorney General in 1853. In 1853, following the large defeat of the Whig candidate General Winfield Scott in the U.S. Presidential election of 1852, Gibson threw his support to the Free Soil Party and began organizing what would become the Republican Party in Ohio. He attended the first organization meeting of the Republican Party in spring of 1856 in Pittsburgh. He was one of the 69 Ohio delegates (of a total 600 delegates from around the country) that attended the first Republican National Convention held in Philadelphia in June 1856. In 1856, he ran and was elected as the first Republican to hold the office of Ohio State Treasurer.