I know that is a tricky concept, and I wouldn't personally use those words, but if you consult human development indices the answer is Asians living in New Jersey. The standard is:
The index factors in life expectancy at birth, educational degree attainment among adults 25-years or older, school enrollment for people at least three years old and median annual gross personal earnings.
What does New Jersey do right? How much of that is selection?:
Across the 50 states and the District of Columbia, Asian Americans were worst off in Louisiana. Their New Jersey counterparts lived an average of nine years longer and earned more than twice that of Asian Americans in Louisiana.
Overall Asian-American life expectancy is 86.6 years. Here's a scary sentence:
Washington, D.C. offered the highest level of human development among whites.
African-Americans fare best in Maryland, which also may be a DC effect. There is this too:
Latinos outlive whites, on average, by over four years, and in all but four states