PHOENIX (AP) — The immigration bill passed by the Senate will achieve 90 percent control of the U.S.-Mexico border and if that doesn’t happen in five years, another $2 billion will be poured into the effort, Arizona Sens. John McCain and Jeff Flake said Tuesday.

That’s one of the key points the Republicans made during a question and answer session with reporters and members of the public during a “conversation on immigration” event sponsored by The Arizona Republic and its media partners in Mesa.

The “Gang of Eight” members pushed their comprehensive immigration reform bill through the Senate earlier this year, but it has stalled in the House. They argued that while they’re concerned about the delay in the GOP-controlled House, they believe there is support for reform there as well and whatever happens, the bill must contain a path for citizenship for the 11 million people living in the U.S. without legal status.

“It’s my view that this legislation has to contain a path to citizenship,” McCain said. “This is an enormously long path to achieve citizenship that is part of this law. Yes, they entered this country illegally, but they will pay a very heavy penalty.”

In a separate interview, Republican Ariz. Rep. Paul Gosar said a bill like the Senate’s that includes citizenship for those illegally in the country won’t pass, and if the House considers a bill that matches the Senate’s, the leadership is at risk.

“Frankly, we are not interested in the Senate bill,” Gosar said. “We are not interested in compromising with the Senate bill.”

“I think if Republican leadership tries to push that Senate bill it will cost them their job,” Gosar said.

McCain and Flake spoke during an event streamed live on the Republic’s azcentral.com website and taped for a Sunday broadcast on 12 News. They took questions from reporters, from the invitation-only audience and from submissions via social media.

A handful of immigration reform opponents waved signs and shouted outside the Mesa Arts Center’s Piper Theater.

One of the audience members who posed a question was Susan Krentz, widow of southern Arizona rancher Robert Krentz, who was gunned down in March 2010 while checking water lines on his property. Authorities believe — but have never produced substantive proof — that a scout for drug smugglers was to blame for his killing.

“A new law no one follows will not secure our border or secure this nation,” Krentz said. “So how long does my family have to wait and others along the border so that we can live and work in peace?”

McCain said he has “tried to assure her and other residents of our state that these measures that we have in this legislation we believe will prevent another tragedy such as you experienced.”

The senators also fielded a question on whether the law will lead to Americans losing their jobs to immigrants. McCain responded with federal estimates that the bill will help the economy and workforce grow.

“I can’t imagine the belief that unleashing 11 million hard-working people into our economy would not be helpful,” McCain said.

On border security, the senators said more technology is needed to identify and stop immigrants and smugglers, and more fencing in the areas where it makes sense.

“It depends on the area, but it’s safe to say that a lot more fencing is needed, a lot more fencing is provided for in this legislation and will be required to be in place before anyone adjusts their status,” Flake said.