Former Congressman Campbell led off describing his five terms in Congress and his service in the Regan administration, while DeVore came out swinging.
"I was glad to hear Mr. Campbell talk about fiscally conservative principals because in fact I don't believe that there's a tax increase in recent history that he hasn't supported," said DeVore.
When asked about his support for the Arizona immigration law, DeVore went after Fiorina.
"One of my opponents, Fiorina, was going all over the map on this issue," said DeVore.
Trailing both Campbell and Fiorina in the polls and in fundraising, DeVore used the debate to get some attention, while Fiorina began by challenging front runner Campbell.
"I'm particularly proud to have signed the tax payer protection pledge the day I announced my candidacy, something Mr. Campbell has refused to do," said Fiorina.
"I appreciate the attention my two colleagues have given me. The only thing better would've been less attention," said Campbell.
All three said the government must secure the borders, they all said they were repeal the president's health care legislation, and all three blamed the government more than Wall Street for the financial crisis. The differences were more around the margins.
"I do not believe in amnesty," said DeVore.
"Neither do I Chuck, as you know," said Fiorina.
"Well, I think we just had some news made here tonight, so perhaps now, all of us are now firmly on the record against amnesty. That's wonderful, that's progress, I'm glad that you moved toward my position," said DeVore.
A question that drew one of the sharpest lines of the night was if people on the no fly list be allowed to buy a gun. Both Fiorina and Devore defended the second amendment right, but Tom Campbell was incredulous.
"I can't believe what I'm hearing," said Campbell.
After the debate Fiorina stressed she is running against Barbara Boxer.
"I focused I believe on the issues and Barbara Boxer and the point here is to actually beat Barbara Boxer," said Fiorina.
Campbell said his focus is on the economy.
"I offer the best opportunity to contrast with Senator Boxer on the issues most important to our state of getting people back to work," said Campbell.
And the assemblyman from Orange County said he thinks Campbell's polling numbers are soft, while his are on the rise.
"The race may begin to be a two person race between myself and Carly Fiorina," said DeVore.
The debate can be seen this Sunday at 11 a.m. on ABC Channel 7.