Texas Sen. Ted Cruz released his birth certificate, and it shows a dual U.S./Canadian citizenship:

From the Dallas Morning News:

Born in Canada to an American mother, Ted Cruz became an instant U.S. citizen. But under Canadian law, he also became a citizen of that country the moment he was born.

Unless the Texas Republican senator formally renounces that citizenship, he will remain a citizen of both countries, legal experts say.

A 2016 slogan based on these facts has already been suggested:

We hope the above information puts things to rest.

Alright, maybe not.