 He started his public life in earnest there, becoming the Harpursville postmaster from 1830 to 1839, a judge in the Broome County, New York court for 8 years, and a member of the New York State Assembly from 1836 to 1837.In 1839, Allen was elected on the Democratic ticket to the United States House of Representatives for the twentieth district of New York for the twenty-sixth United States Congress.He served from March 3, 1839 to March 3, 1841.