Somebody can become president in America without a single vote too, just ask Gerald Ford. Resignations make things muddy for a while in any system.
Except Ford was elected on the presidential ticket in part for said purpose.
These people became President of the United States
without being elected to the office. Usually because
the sitting President died in office President.
John Tyler
Millard Fillmore
Andrew Johnson
Chester A. Arthur
Theodore Roosevelt
Calvin Coolidge
Harry S. Truman
Lyndon B. Johnson
Gerald Ford