What do you mean by a lifelong politician? 20-30 years
Do you mean that the only candidate you want for president is someone with zero experience in any form of government? Because yes, that person would likely have to be rich, and would likely have given huge amounts of money to political campaigns on both sides of the aisle.
George Washington had no political experience and was one of the greatest Presidents of all time. Eisenhower also like Washington, former General.
I can think of a couple people who have done that with varying degrees of success.
Ronald Reagan would be a great example. Unfortunately, he doesn't count. Yes, he was an actor before he was president, but he was a governor for eight years and had already tried and failed to run. His celebrity status is a good analogy for the current Trump bonanza. Some people see another Reagan that was more figurative and a leader. Plus he showed he can do QVC commercials last night...Trump water, Trump steak, Trump wine.
Schwarzenegger and Jesse the mind ventura also had noteworthy private citizen to public service runs. I'll leave it to you to decide if they were successful. Arnold was great in California, he got them to stay within budget. Love Gov Moonbeam but California has a lot of problems financially right now. Ventura seemed like he faded in Minnesota after a strong start.
Ross perot was the closest we've come to having a private citizen go directly into the office of the president. He was demolished in the general election but he had a good run. He sabotaged himself by leaving the race and then returning. Clinton took office with about 40% of the vote so I don't think demolish is the right word to describe it.
The tea party candidates over the lady several years were, by and large, private citizens with no government experience. How do you feel about their presence in the house?
The reality is that the presidency is not a job you can just pick up as you go along. You need to have a lot of real, relevant experience just to attend the training program. You wouldn't hire an outsider to manage the entire produce department at whole foods just because they'd owned a farm, would you?