“The governor, the Legislature, the 174 members who voted for that piece of legislation did not get the choice of whether or not those kids were there,” Mr. Sharp said. “Their choice is whether or not those kids are going to become productive citizens or become one hell of a drag on the Texas economy, and that’s it. It seems that common sense dictates that maybe, from a Texas point of view, we need to make sure they’re not that kind of a drag on the Texas economy.”

He’s echoing Steve Murdock, the former director of the United States Census Bureau, who is now teaching at Rice University in Houston. Mr. Murdock said illegal immigrants made up 6.7 percent of the state’s population and that leaving them uneducated would devastate the state economy by 2040.

Judging from the number of nodding heads in the audience, Mr. Sharp’s line worked in Austin. It might well have fallen flat on the presidential debate stage, though it could hardly have gone worse than the reaction Mr. Perry received.