Last updated at 11:43 p.m. EDT
Alaska Gov. Sarah Palin made a Friday that she is resigning from office at the end of the month without explaining why she plans to step down, raising speculation that she would focus on a run for the White House in the 2012 race.
The former Republican vice presidential candidate hastily called a news conference Friday morning at her home in suburban Wasilla, giving such short notice that only a few reporters actually made it to the announcement. State troopers blocked late-arriving media outside her home, and her spokesman, Dave Murrow, finally emerged to confirm that Palin will step down July 26. He refused to give details about the governor's future plans.
"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," Palin said in a statement released by her office.
"The timing and astonishing nature of Palin's announcement will naturally lead people to assume that there is more to the governor's decision to resign than she has let on, and there might well be," said CBSNews.com producer Scott Conroy, who covered Palin's vice presidential campaign last year.
"But in the months since the Republican defeat in November, the Alaska governor has shown time and again a high level of frustration with the baggage that has come with becoming such a high-profile governor and national celebrity," Conroy said. "Many of Palin's former political allies in Alaska have turned on her, and the near-constant barrage of criticism has clearly weighed on the former vice presidential candidate, as her demeanor during the emotional press conference at her lakefront home in Wasilla attests."
Pam Pryor, a spokeswoman for Palin's political action committee SarahPAC, said the group continues to accept donations on its Web site, with an uptick in funds after Palin's announcement.
The announcement caught even current and former Palin advisers by surprise. Former members of the John McCain campaign team, now dispersed across the country, traded perplexed e-mails and phone calls.
Sen. Lisa Murkowski, R-Alaska, released a statement about Palin's decision Friday evening.
"I am deeply disappointed that the Governor has decided to abandon the State and her constituents before her term has concluded," Murkowski said.
Palin was first elected in 2006 on a populist platform. But her popularity has waned as she waged in partisan politics following her return from the presidential campaign. Her term would have ended in 2010.
More coverage of Gov. Sarah Palin:
Sarah Palin Resigns
Analysis: Palin Was Fed Up
Palin said she planned to make a "positive change outside government," without elaborating. She also expressed frustration with her current role as governor.
"Her stepping down at the end of the month allows her to focus on her future political plans: a run for the 2012 presidency," said CBS News political director Steve Chaggaris. "She won't be restricted by the trappings of a faraway governor's office and the continuing firing squad from her opponents in Alaska, and won't have to worry about a potentially tough gubernatorial re-election bid in 2010."
"It will clear the deck for Palin to focus on raising money and speaking to Republicans around the country as she gears up for 2012," Chaggaris added.
"Going back to Alaska wasn't a safe haven. She sees people like Mitt Romney and Newt Gingrich, who aren't tethered to a political office, getting a head-start. Now she doesn't have to worry about answering to people in Alaska, and be in a more convenient situation to focus on national campaigning and establishing a base, rather being stuck in Wasilla, Juneau or Fairbanks."
Conroy points out that "she still has an enormous base of support among grassroots conservatives, who will continue to come out in droves as she seeks warmer pastures across the Lower 48.
"Though she has a big hill to climb to regain credibility in many circles, those who write off Sarah Palin's political future do so at their own peril," Conroy adds.
CBS News correspondent Nancy Cordes reports that quitting to run for president is a risky and highly unconventional political gamble.
"This is very unusual, very bizarre. Governors don't just step down in the middle of their term," said Politico's Mike Allen.
But leaving the statehouse would give her freedom to travel - and political experience she could never get in Alaska, Cordes reports.
CBS News political consultant John Dickerson said that if she is planning to run for president, her decision does have some downsides.
"Her greatest card used to be to charges that she lacked depth and executive experience that she could point to her role as governor," Dickerson said. "Now, she doesn't have that anymore."
But, if she leaves the role, she can raise money for Republicans and build morale in the party, which will be key if she wants a future in the national party, Dickerson said.
"I cannot stand here as your governor and allow the millions of dollars and all that time go to waste just so I can hold the title of governor," Palin said.
Later, on Twitter, she promised supporters more details: "We'll soon attach info on decision to not seek re-election ... this is in Alaska's best interest, my family's happy ... it is good. Stay tuned"
Palin's decision even took Parnell by surprise. He said he was told on Wednesday evening, and was not aware that any presidential ambitions were behind the move.
Palin emerged from relative obscurity nearly a year ago when she was tapped as then Republican presidential candidate John McCain's running mate.
She was a controversial figure from the start, with comedian Tina Fey famously imitating her elaborate hairstyle and folksy "You betcha!" on "Saturday Night Live."
Most recently, she led a public spat with "Late Show" host David Letterman over a joke he made about one of her daughters being "knocked up" by New York Yankees baseball player Alex Rodriguez during the governor's recent visit to New York. Palin's 18-year-old daughter, Bristol, is an unwed, teenage mother.
Letterman later apologized for the joke.
Palin's family and the ridicule they endure being in the public eye was part of her decision. She complained that her 14-month-old son, Trig, who was diagnosed with Down's syndrome, had been "mocked and ridiculed by some mean-spirited adults recently." She didn't elaborate.
Palin campaigned on ethics reform in the 2006 election, defeating incumbent Gov. Frank Murkowski in the Republican primary and a former two-term Democratic governor, Tony Knowles, in the general election.
She enjoyed an extended honeymoon with lawmakers and voters alike. Her popularity was in the 80 percentile range, even though that fell after the bruising, partisan presidential campaign.
Palin's delivery of two weeks' notice rattles a Republican Party plagued with setbacks in recent weeks, including extramarital affairs disclosed by two other 2012 presidential prospects, Nevada Sen. John Ensign and South Carolina Gov. Mark Sanford.
Ensign, a member of the Christian ministry Promise Keepers, stepped down from the Senate Republican leadership last month after admitting he had an affair for much of last year with a woman on his campaign staff who was married to one of his Senate aides. Ensign later disclosed he had helped the woman's husband get two jobs during the affair.
A government watchdog group, Citizens for Responsibility and Ethics in Washington, wants the Senate ethics committee and the Federal Election Commission to investigate.
Just days after news of Ensign's affair broke, Sanford admitted an affair with a woman in Argentina. Some lawmakers are now calling for his resignation. Before the admission, Sanford had been missing from the state for five days visiting his lover. He had slipped his security detail, lied to his staff about where he was and failed to transfer power to the lieutenant governor in case of a state emergency.
Sanford admitted he also saw the mistress during a state-funded trip to Argentina last year. He promised to reimburse the state for part of the trip's costs. The state Commerce Department said the trip itinerary originally included only Brazil, but the governor requested economic development meetings in Argentina.
The GOP troubles seem to have left two prominent 2012 prospects, former House Speaker Newt Gingrich and 2008 presidential hopeful Mitt Romney, unscathed, however.
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