Democratic presidential hopeful Howard Dean (search) warmed up a crowd of California public school teachers Sunday by brandishing his own short-lived teaching credential.

"I can personally say that I am the only person running for the presidency of the United States that knows what it's like to stand up without being able to go to the bathroom for five hours," Dean said to hearty applause.

Dean, 54, longtime Vermont governor and medical doctor, said he taught eighth-grade social studies for three months.

But that was before Dean reinvented himself as a presidential candidate.

"I disagree strongly with President Bush on virtually every policy," Dean told some 800 delegates of the 330,000-member California Teachers Association (search), which will endorse a candidate.

Besides grabbing headlines by becoming an early Democratic contender to announce his candidacy, Dean has distinguished himself by opposing the war in Iraq, and publicly sparring with Massachusetts Sen. John Kerry (search), at a candidate debate in South Carolina.

Speaking to the teachers, he offered his lesson plan for winning back the White House in 2004.

"The only way that this party will be able to win is to stand up and act like real Democrats," he exhorted the crowd.

Dean said most Americans like Bush because he acts like a leader, while at the same time disagreeing with his policies.

Dean then outlined his policy preferences. He opposes the Bush tax cut, saying it hurts the middle class. He supports early childhood development programs, such as one in his state that sends a social worker to the bedside of every woman who has just given birth. He favors programs that boosts reading in schools and parental leaves of absence.

He said using taxpayer money to support private schools through vouchers is "the real agenda of the president," adding, "public schools are the last institution where everybody gets to meet everybody in America."

Beverly Carlson, who has taught third grade at April Lane School in Yuba City for the past 38 years, said she liked what she heard.

"His comments were to the point and right on the mark about what teachers care about," she said. "He doesn't waffle."

Carlson said she didn't expect Dean to talk about homeland security issues.

"What we need right now is some hope for the future," she said.

Carlson hasn't made up her mind about an endorsement. "I haven't heard the other candidates," she said, "but I like everything he said."