Gov. Sarah Palin announced Friday that she will step down as Alaska's chief executive by the end of the month. She will not seek election to a second gubernatorial term in 2010.
As the 2008 Republican vice presidential nominee, Palin had been considered one of the front-runners for the GOP nomination in 2012.
"People who know me know that besides faith and family, nothing's more important to me than our beloved Alaska," Palin said at an announcement from her home in Wasilla. "Serving her people is the greatest honor I could imagine."
Palin was elected governor in 2006. She was tapped as Arizona Sen. John McCain's vice presidential running mate last year.
Palin said she was transferring authority to Lt. Gov. Sean Parnell, who will be sworn in at the Governor's Picnic on July 26. Video Watch Palin's announcement »
Palin added in a statement that she was "determined to take the right path for Alaska even though it is not the easiest path. ... Once I decided not to run for re-election, I also felt that to embrace the conventional lame duck status in this particular climate would just be another dose of politics as usual, something I campaigned against and will always oppose."
A Republican source close to her political team told CNN's John King that it was a "calculation" she made that "it was time to move on." The governor's "book deal and other issues" were "causing a lot of friction" in her home state, the source said, adding that he believes she is "mapping out a path to 2012."
Another source, speaking on the condition of anonymity, said Palin "thinks she has accomplished goals she has set forward. ... She sees what a positive influence she has had on people's lives from traveling the country in the last year."
Following Palin's announcement, the Democratic National Committee blasted what it called her "bizarre behavior."
"Either Sarah Palin is leaving the people of Alaska high and dry to pursue her long shot national political ambitions or she simply can't handle the job now that her popularity has dimmed and oil revenues are down," DNC spokesman Brad Woodhouse said.
"Either way, her decision to abandon her post and the people of Alaska who elected her continues a pattern of bizarre behavior that more than anything else may explain the decision she made today."
Republican strategist and CNN contributor Ed Rollins said, to a certain extent, Palin's announcement makes her look "terribly inept."
"I think everyone is shocked by this, and I think to a certain extent everyone is going to assume there's another story. You don't just quit with a year and a half to go. You certainly don't do this as a stepping stone to run for president. You finish the job that you're in, and obviously she's not doing that," he said.
"I think people are going to be very suspicious because of the timing. You don't quit on the Friday of a three-day holiday. If you are going to do this, you think it through, you give a good speech," Rollins said.
In an interview last month with CNN's Wolf Blitzer, Palin said she was unsure about her re-election bid because she needed to focus on her state and her family.
This move is just plain stupid. No Governor that has ever, EVER resigned from office, especially 3 years in advance, has never ever been elected President. On the bright side, I can finally say good riddance to this Nowhere Man and move on with my life. Sarah Palin is finished politically IMO. Your thoughts.