Ah, I am disappointed, Timber. I expected statistics, not one single example. One can always find some isolated case of someone achieving a high social raise from a foreign and/or poor origin.
But the reality of the "American dream" cannot be demonstrated without two sets of figures :
- statistics of social mobility (what percentage of people actually achieve the dream, reflecting one's actual chance of fulfilling it)
- figures showing the repartition of income in the population (the global expectancy of wealth of the population)
You can find the latter figures in the World Bank set of statistics
here.
You can see in those figures that, concerning the repartition of income, the USA is the most inequal of the developped countries. So much for the American dream ...
Not to say that the "French dream" is that much better, BTW.
As for the single personal counter-example : the guy I was dating back when I was a student was Italian. He came to France at 6, from one of the poorest parts of South Italy (on the east coast, just opposite Napoli), with his parents, who had both started working at 13. He achieved at least a Master in computer science (maybe more, but we had broken at this time, and I didn't stay in touch). And he didn't have to choose between French and Italian nationality before his majority, and even then, he could choose to keep both, which he did.