The path to citizenship expected to be part of federal immigration reform will be the most important and contentious part of the political debate, say two Arizona politicians.

The U.S. Senate's "Gang of Eight" is expected to unveil its proposed legislation Tuesday morning in Washington. By all accounts, it will include a method for legalizing millions of people now in the United States illegally.

"The single most important aspect is the pathway to citizenship," state Sen. Anna Tovar, D-Tolleson said. "There's over 11 million people here in the United States wanting to achieve a level of citizenship. So I think a clear pathway to achieving that citizenship is a win-win situation for our economy."

Former state legislator Jonathan Paton, a Tucson Republican, said the GOP recognizes that but is involved in debate over paralleling improved border security with the idea of legalization.

"There's a big central debate that's going on within the Republican Party right now about how do you give some sort of legal status to people who are already here, but also ensure that there is border security," Paton said. "Because a lot of Republicans that ran in the last election said they weren't going to deal with anything involving legal status until we secure the border."

The bipartisan Senate proposal is expected to include border security upgrades along with a system for measuring progress on security.

Tovar said there's not universal agreement on the issues, but the fact that the political process is moving is good.

"It'll be a proposal that may not have everything that everyone agrees on," she said. "But I do definitely feel that it is a step in the right direction. It's been many years of discussion, arguing and bickering, and it has definitely been an issue in Arizona, and it's been very divisive. So I'm glad to see that progress has been made."

Paton said one aspect of the proposal that may make it more palatable to Republicans wanting the border secured first is that the penalties immigrants must pay on the path to legalization could help fund security.

"While the plan may be delayed as to when the border is secured, there will be money flowing into it right away, which is a sort of sweetener for people who otherwise might be voting no on the bill," he said.

Paton said it's important for conservatives to see the program pays for itself. "This actually puts teeth into that promise," made during campaigns to secure the border first, he said.

Tovar said the issues of border security and legalization "go hand in hand. We tackle both issues together, simultaneously. I don't think you need one more than the other. I think our border is more secure than it's been in many past years, and I think it's time to move forward from that argument and tackle these issues together."

See Tovar's interview here:

See Paton's interview here: