PORTLAND, Ore. -- The race for Oregon attorney general between "the politician" and "the professor," as they have called each other in low-key insults, has taken a slightly nasty turn with some new attack ads by "the politician" -- Greg Macpherson.

The veteran state lawmaker is challenging fellow Democrat John Kroger, a Lewis & Clark law professor, in a primary that will likely decide the next attorney general because no Republican candidate has filed for the office.

The latest TV ad by the Macpherson campaign paints Kroger as an inexperienced outsider.

"John Kroger has never practiced law in Oregon," the ad says, adding that "while in Oregon he has never protected one consumer from fraud, one family from crime, or one inch of land from development."

Macpherson, a Democratic state representative from Lake Oswego, is a third-generation legislator who claims credit for crime and consumer protection laws, and for passing Measure 49 to change property rights law.

Kroger, a former Marine and federal prosecutor who moved to Oregon to teach law after tackling organized crime and Enron, said Wednesday the latest Macpherson ad is false and misleading.

"It's classic style for attack ads -- riddled with untruths," said Ben Unger, campaign spokesman for Kroger.

Unger said Kroger spent a good deal of time in Oregon on the Enron fraud case because Portland General Electric was its subsidiary and its main asset after bankruptcy.

Unger said Kroger interviewed witnesses, reviewed thousands of documents and helped uncover a "smoking gun" videotape of former Enron CEO Jeffrey Skilling talking to employees in Portland. Skilling was convicted in May 2006 of fraud, conspiracy, insider trading and lying to auditors in the collapse of Houston-based Enron, once the nation's seventh-largest company.

The case involved protecting Oregonians from both crime and fraud, Unger said.

He also said the Macpherson ad is wrong about Measure 49 because Kroger was one of 11,000 Oregonians who volunteered to campaign for the ballot measure, a referral from the Legislature to modify an initiative that caused statewide confusion on property rights after it was approved by voters in 2004.

A previous TV ad by the Macpherson campaign was a takeoff on the popular "Mac vs. PC" ads for Apple Inc. computers, stressing the "Mac" portion of Macpherson's name to make him the cool know-it-all while Kroger is portrayed as the hopeless doofus who cannot come up with a response.

"I protected Oregon families by passing laws cracking down on meth producers and Internet sex predators," Macpherson says in the ad. "I protected a women's right to choose, and I passed measure 49 to protect open space from development."

In reality, Unger said, Kroger had a long and detailed response to similar Macpherson claims during a debate at the Portland City Club.

The ad was criticized by Steve Doell, president of Crime Victims United, who said Macpherson blocked a half dozen sexual predator bills as chairman of the House Judiciary Committee, including a bipartisan bill that would have made it illegal for the state to provide Viagra for convicted sex predators.

"It's like the state funding guns for convicted murderers," said Doell, who supports Kroger.

Macpherson responded with a statement Wednesday that "I unequivocally oppose providing Viagra to sex offenders," saying the proposed bill was unnecessary because the state does not pay for it "and never has."

Macpherson also said Kroger's role in Oregon during the Enron case was mostly research, and noted he was not certified to practice law in Oregon until he passed the state bar exam last September.

Macpherson has emphasized that Kroger has been a professor since he moved to Oregon in 2002 while Macpherson has served three terms in the Legislature.

Kroger has responded to the "professor" label by calling Macpherson "a professional politician" who has never been in court or tried a case.

But the tone of Kroger campaign ads on TV so far has been upbeat and focused on his qualifications, including more than 1,000 courtroom appearances as a prosecutor and his previous work as a public policy advisor in the Clinton administration.