Republican Senator Susan Collins, an independent-minded moderate, won a surprise re-election victory in Maine on Wednesday, strengthening her party's chances of retaining control of the U.S. Senate. Collins, 67, turned back one of the strongest challenges in her career as she defeated Democrat Susan Gideon, 48, the speaker of the Maine State House of Representatives. "I feel that this is an affirmation of the work that I'm doing in Washington to fight hard every day for the people of Maine," Collins told reporters.