Sen. Ted Cruz (R-TX) appeared on "Hannity" tonight to speak about a wide range of topics, including the incredible rise of Donald Trump.

Cruz said that he's friends with Trump, and he offered a theory for why his fellow GOP presidential contender has taken a huge lead in the polls.

"He’s bold and brash, and he’s willing to speak the truth. And he’s taking on the Washington cartel," Cruz said.

He added that Trump's focus on illegal immigration and sanctuary cities has captured the attention of many Americans and set him apart from other candidates.

"I appreciate Donald focusing on illegal immigration," Cruz said. "I've been proud to defend him for focusing on illegal immigration."

Watch the "Hannity" interview above.

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