He served as a Free Soiler in the Massachusetts house of representatives from 1849 to 1853, and was speaker in 1851 and 1852; he was president of the state Constitutional Convention of 1853, and in the same year was elected to the national House of Representatives as a coalition candidate of Democrats and Free Soilers.
In 1852 he was the candidate of the Free-soilers for the governorship of Massachusetts, but was defeated.
First, for many years the Free-Soilers gained strength; then in 1855 in an extraordinary party upheaval the Know-Nothings quite broke up Democratic, Free-Soil and Whig organizations; the FreeSoilers however captured the Know-Nothing organization and directed it to their own ends; and by their junction with the anti-slavery Whigs there was formed the Republican party.
To this the original Free-Soilers contributed as leaders Charles Sumner and C. F.
He was a Whig representative in Congress in 1849-1853, and was leader of the radical Whigs and Free-Soilers, strongly opposing the Compromise Measures of 1850,1850, and being especially bitter in his denunciations of the Fugitive Slave Law.