You can use two curves.
One that traces the outline of the capital. And a bezier circle to control the diameter.

![enter image description here][1]

On the Bezier Circle select the bezier curve as bevel object.

![enter image description here][2]

![enter image description here][3]


You can then convert the curve to a mesh for further editing (<kbd>Alt</kbd><kbd>C</kbd>).

![enter image description here][4]

![enter image description here][5]


  [1]: https://i.sstatic.net/uJaOn.png
  [2]: https://i.sstatic.net/vLSws.png
  [3]: https://i.sstatic.net/yCsu7.png
  [4]: https://i.sstatic.net/mcyD0.png
  [5]: https://i.sstatic.net/UDyK9.png