Gokul43201 said:
It's there in the same link. The likelihood for someone to have a college degree irrespective of location within the US (i.e., averaged over all locations) is specified in the first line of the table.
That gives statistics for the average county, not the average person. In fact, if the percentage of residents with college degrees is only 27%, then there's a good chance the average person doesn't have a college degree.
The average person needs a little definition.
I think it's safe to assume we're talking about the average person in the US (Joe SixPack), which is about 13.3 years of education. (Worldwide, the average person has about 6 years of education.) http://www.oecd.org/dataoecd/56/9/37863998.pdf (you have to scroll down to page 4)
Someone else noted that Washington DC had a lot of people with college degrees, but a lousy school system. The education system of a city or state has little to do with how many college graduates it has. For example, Colorado is below average for its educational system, but ranks near the top in percentage of college graduates. People with college degrees are more mobile than people with little education. People with college degrees move where the jobs are and the jobs are more likely to be located near big cities instead of rural areas. People with only a high school degree or less are more likely to stay put and endure whatever economy their home town is enduring.
In other words, a city doesn't have to develop its own residents into college graduates if it can attract college graduates from other parts of the country. (And the area along I-25 North and South of Denver is starting to resemble California culturally, hence the change from a Red state to a Purple state that's getting ever more Blue.)
This difference is pertinent to a discussion about the Tea Party. If the Tea Party is representing Joe SixPack, his outlook is much different than the outlook of a person that has economic and geographic flexibility. Logically, I'm not sure their differences explain their political positions, but there is definitely a difference.