GREENFIELD, Ind. — At a campaign stop just days before the critical Indiana primary, Heidi Cruz, wife of Republican presidential candidate Ted Cruz, said one of her husband's strengths in the campaign is that he "is an immigrant."

"Ted is an immigrant," Mrs. Cruz said, emphasizing the word "is." "He is Hispanic."

Ted Cruz, who was born in Canada but who is an American citizen by birth, has come under withering fire from rival Donald Trump over his Canadian birth. Trump has questioned whether Cruz is constitutionally eligible to be president. (Most legal experts believe there is no question that Cruz is, but the matter has not been litigated.) And Trump has mocked Cruz, whose given name is Rafael Edward Cruz and whose mother is American and whose father is Cuban, over the circumstances of his birth.

"Rafael! Straight outta the hills of Canada," Trump said at a rally in Connecticut last week. "Was a Canadian citizen until 14, 15 months ago. And then he ran for the Senate. You know, you're registered as a Canadian citizen. He says, 'Oh, I'd never do that.' He never knew he was a Canadian! I can't believe that."

Here is the audio of Mrs. Cruz comments in Indiana Saturday:



Here is a transcript:

We have been unifying this party. Five of those 17 candidates have endorsed our campaign. And different parts of the party. We've been unifying fiscal conservatives. Evangelicals. Young people. Do you know that Ted has been winning the millennial vote in state after state? He's been winning the women's vote in state after state. Ted is an immigrant. He is Hispanic. He can unify this party. We have libertarians joining our cause. I have people everyday from the Democrat party telling that they have re-registered to vote for Ted as a Republican because they understand what he stands for and he represents American values.

Asked later, a Cruz aide said Mrs. Cruz misspoke. "As she has in numerous speeches over and over, Heidi was referring to Ted as being the son of an immigrant," said spokeswoman Catherine Frazier. "That is a story she shares repeatedly on the campaign trail. It is an integral part of his background and personal story, one which resonates with the millions of Americans who share a similar background, and that gives hope to those struggling to climb the economic ladder."*

Mrs. Cruz has had to discuss the issue of her husband's birth before. In January, she appeared on a radio program in Iowa in which she was asked whether she is "sleeping with an immigrant." Mrs. Cruz laughed and said, "There was a funny post on the Internet that the Canadians said, 'Don't worry, he's 100 percent American.' So I think that can partly settle the question." She went on to explain that she believes her husband is a natural-born citizen constitutionally eligible to be president.

*This story has been updated with the Cruz campaign's reaction.