Marco Rubio doubled down on previous charges that Ted Cruz flipped his policy positions to appeal to Iowa voters, but excused his own past reversals in an interview that aired Sunday.

The Florida senator claimed in Thursday's Republican debate that Texas Sen. Ted Cruz, ranked first in the Washington Examiner's presidential power rankings, had changed his views on a variety of immigration policies as well as the Trade Promotion Authority bill, crop insurance and ethanol mandates.

NBC's "Meet the Press" host Chuck Todd asked Rubio if he was not also guilty of many changes of position.

"If circumstances change or you learn something along the way, it's reasonable to say, 'Maybe a different approach will work better,'" said Rubio, currently third in the power rankings.

The former "Gang of Eight" member pointed to immigration policy as an example of a time he sensibly flipped positions on an issue.

"It is clear no comprehensive solution to immigration is going to pass," Rubio said. "It is very clear now more than ever that we are not going to be able to do anything on people that are here illegally until we first prove to people that illegal immigration is under control and America is safe."