clipped from: news.bbc.co.uk 
There has been speculation that Mrs Palin, who is very popular with the Republican Party base, might make a bid for the White House in 2012.
Her resignation means Alaska's Lieutenant Governor Sean Parnell will take over as state governor.
Polls indicated Mrs Palin was very popular in Alaska during the first few years of her governorship, and although her approval ratings have dipped somewhat since her vice-presidential run, she still enjoys widespread popularity in her home state.