According to the Detroit News (here), Cars.com finds that the Camry is the "most American car", based on domestic parts content and popularity.
I suppose it is fair, and congratulations to Toyota for supporting the U.S. economy as much as the Camry does.
But...
If you follow the flow of engineering and the flow of money, the picture is a little different. The Camry has quite a bit of its engineering done in Japan, which means that Japanese engineers are doing the work, not U.S. engineers. Also, the profits from the sale of the Camry flow back through Japan, though the shareholders of Toyota are global.
Consider instead a car designed in the U.S. and built over the border, such as the Ford Fusion, or the Chrysler 300. Yes, it is being bolted together by Mexicans (or Canadians, or even Mexican-Canadians), from parts that flow from all over. However, U.S. engineers and technicians worked on the product, and and the profits flow mostly to U.S. shareholders (and the .gov in the case of Chrysler and GM).
It isn't black and white, and if you buy a Camry, to my thinking it is much better than buying a car designed and built overseas. But if you want to support American engineering and American shareholders, you can do better than Camry.