HOUSTON -- Ted Cruz was born in Canada and Friday a veteran attorney has filed a federal lawsuit challenging the senator's eligibility to be president.

Newton Schwartz of Houston asked the Supreme Court to decide if Cruz's birth to an American mother and Cuban father while they lived in Calgary violates the Constitution's "natural born citizen" requirement.

In this Jan. 14, 2016 file photo, Republican presidential candidate, Sen. Ted Cruz, R-Texas, speaks during the presidential debate at the North Charleston Coliseum in North Charleston, S.C. (AP Photo/Chuck Burton)

Cruz argues that because his mother is American, he became a U.S. citizen at birth. But the Supreme Court hasn't previously considered the eligibility question.

Presidential rival Donald Trump has repeatedly questioned Cruz's presidential eligibility.

The pair squared off during Thursday night's Republican debate. When Trump again raised the issue, Cruz shot back that though the Constitution hasn't changed recently, his polling numbers have -- driving Trump's "birther" questions.

-- The Associated Press