DAYTON, Ohio — Reinforcing his efforts to highlight his image as a reformer, John McCain today named Alaska Gov. Sarah Palin as his running mate.

Palin, who has been governor for less than two years, has a history of taking on establishment politicians. In 2006, she challenged incumbent Gov. Frank Murkowski because of ethical improprieties and cronyism. Before that, she was mayor of Wasilla, Alaska, a city about 40 miles north of Anchorage.

The 44-year old Idaho native, who has lived in Alaska since she was a small child, has a varied background. She is an evangelical Christian, a former television sportscaster, a former commercial fisherman and a runner up in the Miss Alaska pageant. She is a former high school basketball player whose intensity earned her the nickname “Sarah Barracuda.”

She has never held federal office and that will provide a contrast both to McCain and to Democratic vice presidential nominee Sen. Joseph Biden, who has been in the Senate since 1973. The two major-party vice presidential nominees are scheduled to debate on Oct. 8 on the campus of Washington University in St. Louis.