Asa William Henry Clapp, son of wealthy merchant and state legislator Asa Clapp (1762–1848) was born in Portland on March 6, 1805. He graduated from Norwich University in 1823. He engaged as a merchant in foreign and domestic commerce in Portland.

He was elected as a Democrat to the 30th Congress (March 4, 1847 – March 3, 1849). He was not a candidate for renomination. He was a delegate to the 1848 and in 1848 and 1852 Democratic National Conventions.

He then resumed his former business pursuits, also serving as a director of the Maine General Hospital and of the Portland Public Library until his death in Portland on March 22, 1891. His interment was in Evergreen Cemetery.

• United States Congress. "Asa Clapp (id: C000413)". Biographical Directory of the United States Congress.