How many US Presidents, born after the Revolution, had only one American parent?

Several Presidents and VPs had only one American parent. (It gets fuzzy because for a couple of hundred years, women didn't count, and took the citizenship of their husband.) Chester Arthur's father was Irish-born and not naturalized when he was born. VP Spiro Agnew's father was Greek and not naturalized. VP Charles Curtis's mother was native american at a time when they couldn't be citizens.

You need ZERO parents to be citizen if you are born in the USA.

Van Buren was the first U.S. president born in the United States. The presidents preceding Van Buren were born in colonies that later became states. Van Buren was the first to be born after the adoption of the U.S. Constitution.

On June 19, 2008, Obama became the first major-party presidential candidate to turn down public financing in the general election since the system was created in 1976.

He nominated and confirmed Sonia Sotomayor as a Supreme Court Justice. In doing so he was the first president to put a person of Hispanic background into that prestigious position.

Obama's granting of his first television interview as president to an Arabic cable network, Al Arabiya, was seen as an attempt to reach out to Arab leaders.

On September 24, 2009, Obama became the first sitting U.S. president to preside over a meeting of the United Nations Security Council.

On a less related note, in his memoirs- "Dreams from My Father: A Story of Race and Inheritance" Obama ties his mother's family history to possible Native American ancestors and distant relatives of Jefferson Davis. You can't get much more natural born than that!

Other than that, your guess is as good as mine.

hawaii has an odd exception that no other states have. they have two kinds of birth certificates. they have one that is called 'certificate of a live birth'. which is when the baby is born to atleast one american parent in a hospital. the other is a 'certificate of birth'. the latter can be applied to non citizens and babies born not in a hospital. obama has the latter. which means he is either a non citizen, or wasnt born in a hospital. since everyone claims to have seen the hospital records, he must be a non citizen. hes the first non citizen president and no one cares its in violation of the constitution.

I like to think he is American-Kenyan

Technically you wouldn't even need one so long as you are born here.