“Contested primaries are so good for America’s political process!” Sarah Palin wrote back in June 2010 when she announced her endorsement of tea-party challenger Joe Miller’s long-shot candidacy in the Alaska Senate GOP primary.

Now, as a pivotal contest in the 2012 GOP presidential race looms just days away, the former Alaska governor is once again weighing in on behalf of an underdog, telling Fox News Channel’s Sean Hannity Tuesday night that she believes Newt Gingrich is the best choice for South Carolina primary voters.

“If I had to vote in South Carolina, in order to keep this thing going, I’d vote for Newt,” Palin told Hannity Tuesday night. “And I would want this to continue — more debates, more vetting of candidates, because we know the mistake made in our country four years ago was having a candidate that was not vetted to the degree that he should have been, so that we know who his associations and his pals represented and what went into his thinking.”

She appeared to be referring to Barack Obama’s candidacy in 2008.

The move by Palin comes a week after her husband, Todd, told ABC News that he was backing Gingrich in part because of Gingrich’s experience in the House during the 1990s.

Sarah Palin has not yet endorsed a candidate in the broader GOP primary. On the same day that her former running mate, Sen. John McCain (R-Ariz.), announced his endorsement of former Massachusetts governor Mitt Romney (R), Palin told Hannity that she was still trying to decide who to back.

But her move Tuesday is in keeping with her role as a “maverick” within the Republican Party.

It also comes as Palin is upping her public appearances, even as she has declined to make a 2012 White House bid.

The Conservative Political Action Conference, an annual confab of national Republican activists, announced earlier this month that Palin will deliver the closing address at its 2012 conference in Washington next month, marking the first time that the former Alaska governor will appear at the event.

Gingrich responded via Twitter to the news of Palin’s move Tuesday night.

“Thanks @sarahpalinusa for throwing your support my way in the South Carolina primary,” he tweeted along with a link to a video of Palin on “Hannity.”

The endorsement is unlikely to move the needle much in Gingrich’s direction, however. Fully 61 percent of Republicans and GOP-leaning independents say Palin’s endorsement wouldn’t make a difference in their vote, according to a Washington Post-Pew Research Center poll released last week (Other GOP politicians scored similarly).

More respondents said a Palin endorsement would have a positive effect than a negative effect, but not by much--23 to 15 percent.

Polling director Jon Cohen contributed to this report.