As Texas Sen. Ted Cruz gains popularity among Republicans, many have speculated that he'll toss his hat in the ring with a run for president in 2016. But some notable figures on the right are expressing doubt as to whether that's even a possibility.

Over the weekend, Donald Trump expressed his uncertainty about Cruz's eligibility and whether he meets the constitutional requirements that the president be a "natural-born" American citizen. Cruz was born in Canada, the son of a Cuban father and an American mother. “Well, if he was born in Canada, then perhaps not,” Trump said.

Now, popular conservative author and columnist Ann Coulter is weighing in with her own speculation.  “It’s not open and shut,” Coulter admitted during an interview with Geraldo Rivera Monday, adding, “We’re going to have to have some law professors look at it and give us the answer.”

While Rivera erred on the side of caution, Coulter reminded him that former presidential candidate John McCain was born outside of the country in a U.S. territory in Panama.  (Side note: Why does it seem so difficult for the GOP to find a viable candidate actually born on U.S. soil these days?!)

Listen to the full interview segment after the jump!

H/T Mofo Politics, who conveniently keep this running Ted Cruz Presidential Eligibility scorecard for all of us:

- Congressional Research Office: Eligible

- Byron York: Eligible

- Temple University Professor Peter Spiro: Eligible

- Laura Ingraham: “Pretty sure”

- Chuck Todd: Undecided

- Donald Trump: Undecided

- Carl Cameron: Ineligible

- Birther Report: Ineligible