In each of Cannon's recent re-election campaigns, he has been turned into a human piñata for anti-illegal immigration groups who claim he hasn't been tough enough. His opponents in the 2004 and 2006 primaries made immigration their central issue but fell short.

This year, his opponent, Jason Chaffetz, says immigration is behind only energy in the list of issues he gets asked the most about, heading into the Tuesday primary.

Chaffetz is again making the case that Cannon is soft on border enforcement, part of a broader assault on Cannon's record, which Cannon says is misunderstood or willfully distorted.

The candidates share many similarities on the issue: Both say legal immigration needs to be easier and faster, businesses need to be able to make sure they're hiring legal workers and the border needs to be secure. They advocate building the border fence, expanding resources for the Border Patrol, and deploying the National Guard to help with enforcement.

It is the question of what to do with the millions of immigrants already in the country where the two differ.

"I don't want to create a police state by hiring enough cops to go door to door and roust these people out and . . . move them out of the country," said Cannon.

Cannon said he supports a program where undocumented immigrants with no serious criminal record and a good work record could come forward, pay a fine of a few thousand dollars and get a temporary work permit.

Immigrants with a more serious criminal record would be disqualified. Document fraud or identity theft might require a higher penalty, but would not be disqualifying crimes.

The temporary permit would have to be renewed every three to five years for an indefinite period of time, during which the immigrants could apply for a visa.

"I think you need a compassionate program that works in America. I don't want to kneecap the economy by trying to kick everybody out," Cannon said.

Chaffetz has delivered tough talk on illegal immigration - at the state Republican convention he advocated pitching tents and putting up barbed wire. In practice, Chaffetz would be less harsh.

He says removing the incentives to remain in the country, such as jobs, medical care or welfare, would drive many undocumented immigrants back home.

Those remaining could sign up for a temporary permit that would allow them to stay in the country legally for a period of time - he suggests a year to 18 months - to avoid separating families and uprooting lives. Ultimately, they would be sent home and could apply for citizenship.

Those who don't choose to go home would be locked up, in a jail or potentially a prison-style camp, then deported.

Cannon says Chaffetz's proposal is unworkable. He says nobody would volunteer to be deported in exchange for a few months in the country. What you're left with is giving immigrants a pass to stay in the country permanently with no penalties.

He says the Chaffetz position is in line with the House Hispanic Caucus' stance. "What they want is amnesty, and because they can't get a full amnesty what they want is a temporary amnesty, and that is what Jason Chaffetz is proposing," he said.

Chaffetz says that is absurd, and his plan is actually similar to one put forward by the bipartisan Western Governors Association. He would not support a path to citizenship, like Cannon proposes.

"I don't think paying a token fine is adequate. Being an American citizen means something. It's not for sale," he said. "There are too many people like Chris Cannon who like the status quo because it's been good for business."

Where they agree, disagree

* Border Security

Both candidates support building the border fence, hiring more border patrol and using the National Guard to help patrol the border.

* Legal Immigration

Both say more needs to be done to allow those who want to come to the United States to do it legally and quickly.

* Undocumented Immigrants

Cannon supports allowing immigrants with no criminal record to pay a fine and get a work permit, allowing them to stay in the country while they apply for citizenship. Chaffetz would give immigrants a permit, allowing a period of time to tie up their affairs and then return home or face deportation.

* Hiring Undocumented Immigrants

Both candidates believe businesses need to easily and accurately check the legal status of workers. Cannon has also supported special work permits for agricultural laborers sponsored by a business that need workers. Chaffetz does not.

* Birthright Citizenship

Chaffetz supports either a law or constitutional amendment ending the practice of automatically making children born in the United States to undocumented immigrants U.S. citizens. Cannon has said an amendment would be needed, but has not seen language for one he is willing to support.

* Official English

Chaffetz supports making English the official language. Cannon believes immigrants should be required to learn English, but says that making English the official language does not help immigrants learn the language.