"amorous," 1900, perhaps connected with goggle, because the earliest reference is in goo-goo eyes. Use in reference to politics is from 1890s and seems to be a shortening of Good Government as the name of a movement to clean up municipal corruption in Boston, New York, etc. It soon was extended to mean "naive political reformer." Goo-goo as imitative of baby-talk is from 1863.
