The Trump appeal?

Fort Worth Star-Telegram:

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University of Texas professor Daron Shaw, who oversees the Texas Lyceum Poll, said that Trump’s support in Texas stems in large part from the perception that the billionaire dealmaker and negotiator would be a strong leader who wouldn’t let America’s adversaries “run over us.”

“That sense that he’s a strong leader has really been part of his appeal, and in Texas, strong leaders really do well,” Shaw said. “That’s a trait that sells well everywhere, but in Texas it’s especially effective.”
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While the piece seems to focus more on Trump than Cruz, most of the things people are saying about the reason they support Trump would apply to Cruz such as:

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“I’m fed up with political correctness and Republicans who talk a good talk and don’t do anything when they get there,” said Spellerberg, an octogenarian who served for 16 years as mayor of Corinth in Denton County. “I’m just tired of pussyfooting around and want somebody that will stand and fight.”
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I think Cruz still has the edge in Texas and it is a big one since Texas delegates make up one-eighth of the total needed for the nomination.