Cardon said his business background as a "jobs creator" gives him the experience and perspective necessary to fix the nation's finances. He was especially critical of the recent deal to raise the nation's debt limit, saying it solves nothing on a long-term basis.
But Cardon also is counting on voters recalling that Flake, until recently, was a proponent of comprehensive immigration reform. That included not only a guest worker program but also a path to legalize the status of the more than 11 million illegal immigrants already here.
"I oppose amnesty and don't think you can reward those who have broken the law," he told Capitol Media Services. Cardon, who has made the politically obligatory trip to the border, said securing the frontier has to be the precursor to any other discussion.
Cardon sidestepped questions of what he would do about those already here.
"I don't like answering hypotheticals," he said. "I think the first thing you have to do is secure and defend the border."
Flake, who also opposed last year's approval of SB 1070 by state lawmakers, made a sharp turn earlier this year on the whole issue. He said he believes the first priority has to be securing the border rather than a comprehensive measure also dealing with the future of those who crossed the border illegally and the labor needs of U.S. businesses.
"All of us who have pushed for broader immigration reform have realized that we've been down that road and it's a dead end," he said in an interview earlier this year with KPNX-TV. But Flake said the underlying situation along the border also has changed.
"It used to be that those who were coming across the southern border, there were very few of them tied to smuggling rings or to drug cartels," Flake explained. "But now, virtually all of them are."
Cardon said he supports SB 1070 which is designed to give state and local police more power to detain and arrest suspected illegal immigrants.
He also seeks to differentiate himself from Flake on the issue of earmarks, funding for those special projects that members of Congress tuck into legislation.
Flake has gained a national reputation for his opposition. Cardon said he, too, opposes earmarks.
"But I prefer the Jon Kyl approach, which says no earmarks - but if there's a worthwhile project for our state, make the case and come through the front door," he said.
"If it makes sense for taxpayers and Arizona, then let's move forward rather than disarm and allow some other states to use our hard-earned dollars," Cardon continued. "We're a donor state," sending more money to Washington than comes back in federal projects.
Flake, who has been running for months, announced last month he already has $2 million in the bank. Cardon said he is undeterred.
"God's been really good to me," said Cardon, whose business, Cardon Investments, puts money into other companies and developments. And he acknowledged that he had some family money - his grandfather founded Cardon Oil - that gave him a financial base.
"I'm going to invest in my candidacy and I'm going to ask others to do so as well," he said. Cardon said he has heard "several different figures" about what a race like this might cost but won't detail his budget.
"Money won't be an object in this race," Cardon said. "I won't be outworked, I won't be outspent, and I'll have the resources to win."
He already has lined up consultants and pollsters who have worked for other Arizona politicians, including Doug McAuliffe who has done work for Kyl.
Flake released a statement noting that U.S. Senate seats do not open up in Arizona that often.
"I certainly never expected to be the only candidate in the race," he said. "Wil's a friend and has been a longtime supporter and I'm looking forward to a healthy debate about the future of our country."
So far the Democrats have yet to field a candidate for the open Senate seat.
It was assumed last year that Congresswoman Gabrielle Giffords would be the party's standard bearer. But the January shooting, while increasing her statewide name ID, also has raised questions of whether she will be able to wage a statewide race.
One issue on which the pair apparently agree is their opposition to the debt extension measure approved by Congress. Cardon said the plan, which Flake voted against, never achieved the Republican goal of "cut, cap and balance."
"They haven't cut, and if cuts do happen, they're years down the road, if ever," he said. And the debt limit was not capped, "with nothing to stop from raising it in the future."
Nor was the budget ever balanced. "It's a credit card economy," he said.
Cardon said he realizes as a businessman that the only way to bring the books into balance is by cutting expenses.
He acknowledged that there are other alternatives, including allowing the Bush-era tax cuts for the wealthiest to expire at the end of next year. Cardon said that's not an option for him.
"That's not how you create jobs, that's not how you strengthen the economy," he said.
Cardon, who turns 41 next month, has been married for 19 years to his wife, Nicole. They have five children.