By Kurtis Lee, Los Angeles Times (TNS)

The back and forth over immigration between Sens. Marco Rubio of Florida and Ted Cruz of Texas has intensified since Tuesday’s Republican presidential debate with daily attacks and a flurry of television ads.

Sunday was no different.

Rubio, who has been repeatedly questioned over his 2013 support of a major immigration reform bill that would have provided a path to citizenship to people in the country illegally, has looked to highlight an amendment to the legislation that Cruz proposed. It would have scrapped the bill’s pathway to citizenship for immigrants who are undocumented but left open a route to legal status in the form of green cards.

“Ted was open, and was in fact a supporter of legalizing people that were in this country illegally,” Rubio said Sunday in an appearance on CBS’ Face the Nation. “He made it clear on multiple occasions that he was against citizenship, but he was open to legalization.”

Speaking to reporters last week in Las Vegas, Cruz insisted the amendment was meant as a sort of poison pill to the bill and that he has never supported legalization.

“I oppose amnesty. I oppose citizenship. I oppose legalization,” he said.

In an effort to push back against criticism, Cruz has highlighted the support of several conservatives, such as Sen. Jeff Sessions of Alabama and talk radio host Rush Limbaugh, who have called Rubio’s attacks misleading.

Surveys of Republican primary voters have shown they strongly oppose granting citizenship to those in the country illegally. Cruz has sought to capitalize on that view.

He’s often assailed Rubio, who was one of eight senators to craft the 2013 proposal, as a supporter of amnesty. A new television ad released in Iowa on Friday hammers Rubio for his support of the bipartisan proposal.

“He still supports amnesty and citizenship to this day,” Cruz said while in Las Vegas, noting Rubio’s concession that he supports allowing some immigrants to apply for work permits and then, after 10 years, allowing them to apply for citizenship.

©2015 Los Angeles Times. Distributed by Tribune Content Agency, LLC.

Photo: Republican U.S. presidential candidates (L-R) Governor John Kasich, former HP CEO Carly Fiorina, Senator Marco Rubio, Dr. Ben Carson, businessman Donald Trump, Senator Ted Cruz, former Governor Jeb Bush, Governor Chris Christie and Senator Rand Paul pose before the start of the Republican presidential debate in Las Vegas, Nevada December 15, 2015.    REUTERS/Mike Blake