I also don't think you can draw a distinction between Mexican immigration and immigration from South and Central America which flows through Mexico" -Annise Parker
Although Mexicans are the majority, many nationalities cross over through the Mexican- American border. Central Americans, South Americans, and even Asians have traveled through the desert all equally searching for the American Dream.
The percentage of Latin American immigrants in the US in 2007
"The United States has always been regarded as a nation of immigrants. Recently-published figures from the United Nations support this view. More than 45 million immigrants live in the U.S., according to UN figures, more than 4 times as many living in any other nation in the world." -Alexander E.M. Hess and Thomas C. Frohlich USA Today