In other hotly contested primaries Tuesday night, a Democratic establishment pick and a Tea Party favorite sailed to victory Tuesday in high-stakes primary contests brimming with big-name endorsements.
In Colorado's Senate primary, one of the most closely watched races, President Obama's pick, Michael Bennet, withstood a bruising primary challenge from Andrew Romanoff, the former state house speaker who was endorsed by former President Bill Clinton.
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Palin's last-minute campaign trip to Georgia Monday to lift Handel proved unsuccessful as the former Georgia secretary of state conceded defeat after a bitter battle for the Republican Senate candidacy.
"As of this morning, we are four-tenths of a percentage point behind Nathan Deal with absentee ballots and overseas military votes yet to be counted. We certainly have the option of requesting the automatic statewide recount. But we are not going to do that," Handel said in a statement today. "The best thing for our party is to rally around Congressman Deal as our nominee in the fight against Roy Barnes."
Deal had the backing of the NRA and some other potential 2012 presidential candidates in Mike Huckabee and Newt Gingrich, both of whom campaigned for him.
Democrat Bennet emerged as the decisive victor in the primary for his seat. The former businessman was the White House's favored candidate even though he was appointed to the Senate and had never seen his name on an election ballot before Tuesday night.
Clinton, who knows Romanoff personally, did not actively campaign in Colorado but recorded a last-minute robo-call for Romanoff.
Republicans are likely to target Obama's endorsement for Bennet in the November elections, as well as his votes for the $787 billion stimulus package and the controversial health care bill.
"I think we're going to unify the Democrats because we've got a positive message," Bennet said on "Good Morning America" today. "The Republican talking points are just not going to get us where we need to be."
But Bennet wouldn't say if he would continue to seek Obama's support in the coming months, saying his campaign will "have to give it some thought."
"We'll obviously have to do what's right for the campaign. ... We appreciate his help," he said. "We'll see what happens between now and November."
On the Republican side in Colorado, Ken Buck, a county attorney, defeated Jane Norton, the former lieutenant governor.
Buck had the nod of strict conservative Sen. Jim DeMint, R-S.C., and Norton had gotten praise but no endorsement from Palin. Norton also campaigned with Sen. John McCain, R-Ariz., the 2008 Republican presidential nominee.