WASHINGTON — Alaska Gov. Sarah Palin is stepping down, announcing Friday that she will pursue other means of having an impact in the public arena, fueling speculation about her intentions for another bid for national office.

She remains popular among the most conservative base of the GOP. But she carries high negative ratings among the general public, according to the latest polls, questioning the role she might play in 2012.

Minnesota Gov. Tim Pawlenty, who had been considered another possibility for John McCain's 2008 running mate, also has announced he will not seek another term — setting up the more moderate Midwestern Republican as another 2012 prospect.

Republican Mitt Romney has rehabilitated a tattered image following the long campaign in which he sought his party's presidential nomination last year.

But Palin still suffers from a sharply divided opinion of her among the American public, following that same presidential campaign — though the Alaska governor remains a rock star within her party, more popular among Republicans than former Massachusetts governor Romney.

These are among the findings of a new Pew Research Center study on the favorability ratings for leading Republicans.

Romney's ratings have improved among the general public, with 40 percent rating him favorably, 28 percent unfavorably. This marks a reversal from February 2008, in the heat of the GOP campaign in which Romney was challenging McCain for the party's presidential nomination — then it was 44 percent unfavorable, 30 percent favorable.

"Impressions of Sarah Palin have not changed much since the presidential campaign," Pew reports. The Alaskan "continues to be divisive figure among the general public, with about as many saying they have an unfavorable impression (44 percent) as a favorable view (45 percent) of the Alaska governor. That's a little better than Palin looked to the general public in October, when her image and her ticket were taking a beating.

But among Republicans, Palin has a 73 percent favorable rating, with just 17 percent viewing her dimly. Only 10 percent offered no opinion.

By contrast, Romney draws a 57 percent favorable rating within his party and 18 percent unfavorable — with 24 percent voicing no opinion.

And former House Speaker Newt Gingrich of Georgia draws similar ratings, 55 percent favorable, 22 percent unfavorable, with the same number uncommitted.