Clinton has been making the campaign rounds recently, stumping for house and senate candidates.
Wednesday night, he told the crowd of several thousand people at A-S-U why they should vote for Richard Carmona.
"I can’t think of a person in America, without regard to party, who is more needed at this moment in our history in the U.S. Senate," the former President told the crowd.
For his part, Carmona said he was thankful the 42nd president came to Tempe…calling Clinton “probably the most famous guy in the world.”
"To come and help me, I’m humbled and I’m so grateful that he’s coming out to help me to bring all these people here so that they can hear our message," Carmona said.
But Carmona's rival 6 term Republican Congressman Jeff Flake dismissed the former president's visit.
"If I were Richard Carmona, I’d certainly welcome it…and it helps, I think, for about an hour," he said.
Flake says the endorsement helps underscore part of his message.
"Richard Carmona has this kind of aura, or tries to put out that he’s an independent, he’s not really a Democrat or Republican. This puts him firmly in the Democratic camp," Flake said.
Recent polls have shown the race to be close…but neither candidate says they’re surprised by how close it’s gotten.