In war, you can only get killed once. In politics it can happen over and over.
I am President Laura Roslin. I wasn't elected, but it wasn't my choice.
I was the Secretary of Education to President Adar and worked with him since he was a Mayor. Prior to attending the decommissioning of the Battlestar Galatica I was diagnosed with breast cancer and informed it was untreatable.
During the latter part of the Cylon attack on the colonies, I responded to an automatic beacon, and was later informed that I (the 43rd in line) was the first (and presumably only) person in the line of succession to respond.
I was sworn in by a priestess on board the ship. Sadly that woman has passed on, but before she did, she guided me to the Pythian scrolls. Prophecies which foretell of a leader to bring humanity to Earth.
I had the visions and I will take us there.