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DALLAS (CBS11) – The political question whether Texas Senator Ted Cruz can be President may now become a legal drama, too.

Houston attorney Newton Schwartz filed a federal lawsuit against Cruz asking the judge to declare the Republican presidential candidate ineligible to become President. “Just real simple. A one sentence ruling. He is eligible and is natural born citizen or he is not a natural born citizen.”

Schwartz said the Supreme Court hasn’t defined what a natural born citizen is.

He wants the ruling before the first in the nation Iowa caucus February 1.

But attorney Chad Ruback, who handles appellate and Constitutional issues, says he doubts that will happen because typically, these kinds of cases take months, if not years to conclude.

SMU Political Science professor Matthew Wilson believes there’s already a consensus among Constitutional scholars that Cruz is eligible.

Cruz was born in Canada, but his mother is American.

Wilson downplays the impact the issue will have. “I think the political impact will be pretty minor. The birther issue is not going to hurt Ted Cruz anymore than the birther issue hurt Barack Obama or John McCain.”

As for Cruz, he calls this settled law.

But billionaire Donald Trump raised the question during Thursday night’s debate. “If you become the nominee, who the hell knows if you can even serve in office? So you should go out, get a declaratory judgment, let the courts decide.”

Cruz was ready with a response. “My friend Donald Trump said that he had his lawyers look at this from every which way, and there was no issue there. There was nothing to this birther issue. Now, since September, the Constitution hasn’t changed. But the poll numbers have.”

Wilson says Cruz became the first Republican candidate to get the better of Trump during the debate, but says neither scored a knockout blow against the other.

The issue comes more than two weeks before the Iowa caucus, and the race between Cruz and Trump is growing tighter.

On Friday, the Real Clear Politics average of polls shows Trump re-taking the lead from Cruz with 27.3 to 26.9 percent.

Wilson says, “I think there will be a tight battle between Cruz and Trump down to the wire in Iowa.”

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