Texas Sen. Ted Cruz claimed Florida Sen Marco Rubio has betrayed his constituents and Donald Trump has hidden his record.
Cruz responded to criticism from rival GOP presidential candidates in remarks to reporters in South Carolina.
Rubio has argued that Cruz is a calculating politician, something Cruz described as preposterous.
"When Marco went to Washington, he broke his word and promptly joined with Barack Obama and Harry Reid and Chuck Schumer to lead the fight to pass amnesty," Cruz told reporters. "You want to talk about calculated? That is the essence of calculated: Looking at the people who elected you, making a promise, and then breaking a promise. Why? Because the big money donors in Washington, because the Washington establishment supports amnesty. That was a calculated move and that was not a move that gives any comfort to the American people that they can trust a candidate to do what he says and the difference is I honored the commitment. It is not calculated for someone to do what he said he would do, to actually fight against amnesty and successfully defeat amnesty, which is exactly what we did."