There are more than you would think. Maybe 10-15% of the class my wife graduated with had done something between college and med school.
The application process is grueling, but the real challenge is living without any real income for 4 years while attending all the necessary classes. Working your way through is not a real option, nor is part time classes. We wouldn't have made it through without some significant help from our family. We managed to graduate with only a modest amount of debt which we aggressively paid off, but most med school grads are so far in the hole that they will likely retire before paying off their student loans.
Surprised to hear that about the loans. I knew someone who lived on about half of his income and paid off his loans in 2 years after his 4 year residency. Now he works part time and spends time with the family and lives very comfortably.