In just about every field I looked at, having a successful parent makes you way more likely to be a big success, but the advantage is much smaller than it is at the top of politics.
Using the same methodology, I estimate that the son of an N.B.A. player has about a one in 45 chance of becoming an N.B.A. player. Since there are far more N.B.A. slots than Senate slots, this is only about an 800-fold edge.
Think about the N.B.A. further. The skills necessary to be a basketball player, especially height, are highly hereditary. But the N.B.A. is a meritocracy, with your performance easy to evaluate. If you do not play well, you will be cut, even if the team is the New York Knicks and your name is Patrick Ewing Jr. Father-son correlation in the N.B.A. is only one-eleventh as high as it is in the Senate.
Emphasis added by me. And this:
An American male is 4,582 times more likely to become an Army general if his father was one; 1,895 times more likely to become a famous C.E.O.; 1,639 times more likely to win a Pulitzer Prize; 1,497 times more likely to win a Grammy; and 1,361 times more likely to win an Academy Award. Those are pretty decent odds, but they do not come close to the 8,500 times more likely a senator’s son is to find himself chatting with John McCain or Dianne Feinstein in the Senate cloakroom.
That is all from Seth Stephens-Davidowitz.