Former Alaska governor Sarah Palin ended her months-long flirtation with a presidential bid Wednesday, announcing in a letter to supporters that she will use her influence next year to help elect Republicans from statehouses to the White House.

Palin’s announcement, which also cited the needs of her family, ends nearly a year’s worth of media speculation about her political aspirations that she fueled with regular public comments and posts on Twitter and Facebook — and with a high-profile bus tour over the summer that included stops in key early-voting states.

Among the questions now are whether she will choose to play a role in winnowing the Republican field or confine herself to remaining one of President Obama’s chief adversaries. GOP strategists said Wednesday that Palin’s popularity with tea party activists and her fundraising prowess would help any candidate with whom she aligns herself. Candidates quickly started sending out complimentary statements after Palin’s announcement, suggesting that the courtship for her endorsement has begun.

“Sarah Palin is a good friend, a great American, and a true patriot,” Texas Gov. Rick Perry said in a statement. She will “continue to be a strong voice for conservative values and needed change in Washington,” he added.

Palin’s decision did not come as a surprise to most political strategists, who believed it was too late for her to build a winning organization so close to January, when primary voting is expected to begin. In that respect, the news ends an era for Palin, who rocketed to stardom after being chosen by Sen. John McCain (R-Ariz.) as his running mate in 2008 and since then has become something of a cultural phenomenon. Speculation about whether she would run again for national office has never stopped.

Yet some Republicans — and Palin herself — said the announcement also represents a new beginning, allowing the Fox News commentator, tea party favorite and prodigious fundraiser to continue wielding political influence through the 2012 election cycle.

“You’re unshackled, and you’re allowed to be more active,” Palin said in a radio interview with Mark Levin. In a letter to supporters read aloud on Levin’s show and later posted on Facebook, Palin said: “We need to continue to actively and aggressively help those who will stop the ‘fundamental transformation’ of our nation and instead seek the restoration of our greatness, our goodness and our constitutional republic based on the rule of law. In the coming weeks, I will help coordinate strategies to assist in replacing the president, retaking the Senate and maintaining the House.”

Palin’s decision virtually seals the Republican field after months of uncertainty about who else might jump in. More than in past years, the nominating contest thus far has been characterized by an unsettled electorate that has yet to coalesce around a single candidate. Voters have bounced from one favorite to the next, and donors have pleaded with leaders who had already said no.

With Palin’s announcement Wednesday — just a day after New Jersey Gov. Chris Christie reaffirmed his own decision to sit out the race — those pleas are probably finished.

“Republican voters may not be settled, but the Republican field is,” said GOP strategist Alex Castellanos, who supported Mitt Romney in 2008 but is uncommitted so far this time around. It’s time to “start the game,” Castellanos added. “Play ball.”

Romney has emerged as the front-runner, but his support is not deep, largely because of conservatives’ reservations about his moderate positions on some issues — and his advocacy for health-care reform while governor of Massachusetts. Other candidates, including Perry and Rep. Michele Bachmann (R-Minn.), have soared in popularity — and just as quickly fallen — as voters have looked for an alternative to Romney.

News of Palin’s decision elicited a variety of reactions from Republicans, some of whom said she made the only possible choice given that most GOP voters, according to polls, had already decided they didn’t want her to run. Some Republicans were critical of Palin’s flirtation with a presidential bid, which they viewed as a thinly veiled effort to retain her celebrity.

“Palin had everything to lose by running,” said Mark McKinnon, a GOP strategist who worked for McCain in 2008. “Now she preserves her celebrity status, her power to generate fees and her ability to be a king and queen maker with her political support and PAC money.”

For months, Palin has been stoking rumors that she would get into the race, launching a flashy “One Nation” bus tour that took her to New Hampshire and Iowa, telling Newsweek she could win, and taking shots at President Obama on Facebook and Twitter. But she never built the kind of political operation considered necessary for a serious campaign.

As time passed, she kept pushing back her own personal deadline, at first saying she would decide by the end of the summer, then by the end of September, then October or later.

“She has her own political base, she certainly generates media attention, and she can raise money,” said Ed Rollins, a strategist for Bachmann. “There’s no doubt in my mind, if she had started a year and a half ago, she could have been a serious candidate. But it would have been thrown together. I don’t think it’s possible for her to have done it now.”

Rollins added that he wouldn’t be surprised if Palin runs for president down the road — or for one of Alaska’s Senate seats. But even last week, Palin cast doubt on that possibility, expressing doubts about a campaign in an interview with Fox News’s Greta van Susteren. She said a campaign might be “too shackle-y” for “someone like me, who’s a maverick — you know, I do go rogue and I call it like I see it.”

While she maintains a loyal fan base, Palin reached a tipping point in polls months ago. Had she gotten into the race at this late stage, she would have been a second-tier candidate at best. She polls in the single digits, gets mixed reviews on her leadership qualities even among Republicans, and performs poorly against President Obama in head-to-head matchups.

In the latest Washington Post-ABC News poll, 66 percent of Republican and GOP-leaning respondents said they did not want Palin to run.