Groups opposing undocumented workers have long portrayed Rep. Chris Cannon, R-Utah, as an arch enemy sympathetic to illegals. But Cannon is now depicting himself in a mail ad as just the opposite, as a tough enforcer seeking deportation.

"Come to America, but come here legally," says the ad that includes a picture of a fence and the Mexican border. While listing numerous enforcement actions Cannon supports, it adds, "Cannon wants to replace catch and release' with catch and deport."'

Has Cannon undergone an election-year conversion amid attacks from GOP primary election challenger Jason Chaffetz that Cannon is too soft on immigration?

"No. I have been consistent," Cannon said. "I have always been hard-core (on enforcement). My voting record is perfect on enforcement. ... I am in favor of protecting our borders." He says Chaffetz is actually the one who is changing and has moderated his earlier stands.

Chaffetz, in turn, said he's kept the same "reasonable but tough" approach throughout his campaign. It's Cannon, he says, who's flip-flopped.

"There is nothing in the record to reflect that (Cannon's) been consistently tough on immigration," Chaffetz said. "He gets tough on immigration about two weeks before an election. That's it."

Regardless, Cannon's new ad sent to voters in his district does not mention the one stand that has brought opposition from groups opposing undocumented workers: support for a "temporary guest worker" program.

In fact, when President Bush gave a 2004 speech to propose allowing illegal aliens to achieve renewable, temporary legal status as a possible pathway to citizenship, Cannon was among a few whom the White House invited to cheer on the president in person. Since then, Cannon has been seen as a leader in Congress for that proposal.

"I still support that," Cannon said, and he has been pushing it in an agricultural bill. But he says he also believes immigration laws must be enforced — and says he surprised some in Congress by taking tough stands on that while still favoring a guest worker program. He adds that those here illegally must pay a price.

"I have always believed there should be some kind of penalty for people who break the law," and said illegals who participate in a guest worker program would need to pay a fine or meet other penalties — with no true amnesty allowed for them.

He said he has been "agnostic" about whether America should require such people to return to their home countries before they can apply for U.S. citizenship.