The 2006 Wisconsin gubernatorial election was held on November 7, 2006. Incumbent Democratic Governor Jim Doyle ran for re-election to a second term in office. He was unopposed in the Democratic primary, and faced U.S. Representative Mark Green, who was unopposed in the Republican primary, in the general election. The campaign between Doyle and Green was competitive and hotly contested, but Doyle, whose approval ratings hovered around 50%, had the upper hand. In the end, Doyle defeated Green by a fairly comfortable margin, improving on his 2002 victory in the process.
Doyle became only the third Democrat to carry Door County; the only two previous gubernatorial elections in which it had voted Democratic were 1859 and 1904. Door County would not vote Democratic again until 2022. Doyle was also the first Democrat since Albert G. Schmedeman in 1932 to win Monroe County.
As of 2024, this is the last gubernatorial election in which the Democratic candidate carried the counties of Adams, Barron, Buffalo, Burnett, Chippewa, Clark, Dunn, Forest, Iron, Jackson, Lafayette, Lincoln, Marathon, Monroe, Oneida, Outagamie, Pepin, Pierce, Polk, Price, Rusk, Sawyer, St. Croix, Washburn, Winnebago, and Wood.