Marco Rubio on Sunday dismissed attacks from opponent Ted Cruz comparing his immigration record to that of President Barack Obama's, saying "it doesn't matter" because "people didn't care about it."
The ad splices together clips of Rubio speaking on immigration reform with nearly identical clips of Obama, hammering Rubio on an issue that's dogged him with conservatives since his role in the 2013 immigration reform effort.
It's part of a protracted effort by Cruz and his allies to paint Rubio as the "Republican Obama." And on the trail, there's evidence the attacks have taken their toll — Rubio is asked about the immigration issue every few town halls, from voters wanting him to clarify his involvement in the 2013 "Gang of 8" reform bill and in particular its inclusion of a path to citizenship.
But Rubio said on "Meet the Press" that not only does the ad not matter, "I can put the exact same ad on about Ted Cruz."
"Ted Cruz said he wanted to find a compromise. Ted Cruz said he wanted to bring 11 million people out of the shadows. Ted Cruz said that he wanted immigration reform to pass," he said.
Cruz has said that many of his amendments to the bill at the time were actually intended as poison pills meant to take the reform bill down. But their differences on immigration reform are sure to take center stage in what's become an increasingly nasty fight in recent days as the two battle to be the alternative to Trump. With the race rapidly turning into a three-man battle between Rubio, Cruz and Donald Trump, Rubio will have to contend with the real-estate mogul as well.
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Asked how he'll win over Trump's voters, Rubio noted that up until now, the anti-Trump lane of the primary had been fractured, and he also said that he'll offer specifics where Trump has not. "We're also optimistic about the future, but only if we do a few things. And I'm going to tell you exactly what those things are. And that's a big difference in this campaign between Mr. Trump's campaign and mine," he said. "And I think that's going to begin to matter a lot more now because there are less people in the race and more time to pay attention to some of that."
This article originally appeared on NBCNews.com.