Immigration reform has divided Sens. Ted Cruz (R-Tex.) and Marco Rubio (R-Fla.). But in an interview with the Houston Chronicle, Cruz said he respected his colleague's effort even if he opposes some of his ideas.

"Marco has worked very, very hard to tackle the very difficult problem of how to fix our broken immigration system," Cruz said. "And I think he has worked in good faith in a sincere desire to craft a solution as to how to approach immigration."

Cruz also called Rubio "a good friend" and "one of the strongest leaders on the national scene," while reiterating his opposition to a "pathway to citizenship" for illegal immigrants. An adviser to the senator told the Daily Beast that Cruz is not going to support "the path they've gone down" on immigration reform, but that he will "focus on the flaws of the details rather than attacking it on the big picture.”

Rubio is a member of the bipartisan "Gang of Eight" that set that path and has been working to convince conservatives to join him.

Both senators are considered potential presidential candidates in 2016. Earlier this month, the National Review reported that Cruz is seriously considering a bid. Both are conservative Cuban Americans with ties to the tea party movement. If Cruz becomes a leader in the fight against immigration reform, it would be a dividing line in the Republican primary. And Cruz has shown himself to be the kind of senator who isn't afraid to criticize his fellow Republicans; at a recent FreedomWorks rally he mocked moderate senators as "squishes" on gun rights. So far, when it comes to immigration, he's holding his fire.