Reflecting on advances in technology, the spread of democracy and defeat of the Soviet Empire, he said he remains “deeply optimistic about America’s future.”

“None of these extraordinary developments happened by accident. In fact, to a significant degree I would say they were made possible by the principled leadership of the United States,” he said.

He also thanked his wife, family, colleagues, campaign workers and volunteers, and specifically included the Capitol Police and maintenance staff.

Updated at 9:34 a.m. on Dec. 13.