Obama took a break from his debate preparations at a Las Vegas-area resort to drive to Henderson with six pizzas from Sette Bello.
"Oh my God!" several of the 20 or so campaign workers in the campaign office squealed when the president walked in. The group broke into cheers and clapping.
"What's going on everybody?" Obama asked. "I'm going to go around. I want to meet every single person."
The Democratic president, dressed in a blue-and-white checked button-up shirt with the sleeves rolled up, tan slacks and brown dress shoes, gave each worker a hug and asked them their names.
"Hi, I'm so excited. I love Michelle," one woman told him.
"I know everybody has been working really hard," Obama said, adding that with 36 days left in the race, "it's really coming up quick and obviously Nevada is going to be critical to this fight. Nevada's going to be close. It's going to be close all across the country. And obviously we've got the debates coming up. There are going to be a number of other things we can't expect over the next couple of weeks."
He told the workers to keep reaching out to voters and knocking on doors.
He said their efforts are very important to the success of his policy agenda, mentioning Wall Street regulations, winding down the Afghanistan war and housing.
"I don't mean to put too much on your shoulders," Obama joked, adding he hopes they are "having some fun along the way" while making friendships and forming bonds.
He said he doesn't "want to let you down."
"We're gonna get this done. We're gonna win," Obama said.
After taking a couple of group photos, the president sat down at a table with two cellphones to call volunteers.
"This is very exciting," Obama said as he dialed.
"Hi, Donna. This is Barack Obama, how are you. ... You've been so helpful," he said to one recipient of a call. "You've been working so hard even though you've got some health issues."
He then called a team leader, Schelia Shinno, and complimented her as "the backbone of this campaign."
He told a third volunteer, Andrea, that this is his last campaign "so we want to leave it all on the table and work as hard as we can."
She apparently asked him about his debate preparations.
"We had a great prep, and it was a lot of fun," he said. "Although basically they're keeping me indoors all the time. It's a drag. They're making me do my homework."
Obama campaign spokeswoman Jen Psaki said the campaign received its 10 millionth donation Sunday and touted the new TV campaign ad out Monday criticizing Republican nominee Mitt Romney on China.
White House press secretary Jay Carney defended Obama's foreign policy record, responding to Romney's criticism of the president's relationship with Israeli leaders. Carney said Obama "has established the strongest relationship with Israel" when it comes to security.
Psaki said Romney engaged in "a lot of chest-pumping rhetoric" without "a lot of specifics" in a Wall Street Journal op-ed piece, adding, "We don't think that's what the American people are looking for."
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