It was either Garfield or Grover Cleveland, I always mix up those two.
James Garfield went from the House to the Presidency. And was shortly after assassinated. His VP Chester Arthur had never been elected to anything prior to becoming VP.
Grover Cleveland was the only Democratic President of that era and is the only President to serve two non-consecutive terms.
In a fashion Gerald Ford also went from the House to the Presidency.
Garfield