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Sarah Porter is a politician from Gemenon, who is selected to represent her colony on the Quorum of Twelve (Colonial Day). During her tenure, Porter appears to be a significantly influential presence within the Quorum.
She initially supports the nomination of Tom Zarek as a candidate for the Vice Presidency. This is possibly a move to spite President Roslin after she refused a request from Porter for additional water supplies over and above the agreed quotas (Colonial Day).
Being from Gemenon, she is very familiar with the Sacred Scrolls and was able to confirm President Roslin's claim that she was the dying leader mentioned in the Pythian Prophecy who would lead the fleet to Earth. This seems to have softened her political grudge against Roslin (Fragged).
Later, Sarah clashes with President Roslin, when Rya Kibby seeks to have an abortion, which is her last known clash with Roslin (The Captain's Hand) before Gaius Baltar's ascendancy to Roslin's position (Lay Down Your Burdens, Part II).