By 1848 Wilmot was thoroughly identified as a Free Soiler, but, like many other Free Soilers, he did not oppose the expansion of slavery based on a legal rejection of the short-term existence of the institution itself. In a speech in the House, Wilmot said, "I plead the cause and the rights of white freemen [and] I would preserve to free white labor a fair country, a rich inheritance, where the sons of toil, of my own race and own color, can live without the disgrace which association with negro slavery brings upon free labor." Around the same time, however, Wilmot, in a New York speech, spoke of the ultimate demise of slavery when he argued, "Keep it within given limits …and in time it will wear itself out. Its existence can only be perpetuated by constant expansion. … Slavery has within itself the seeds of its own destruction."