(CNN) -- Sen. John McCain announced Alaska Gov. Sarah Palin as his vice presidential candidate Friday, calling her "the running mate who can best help me shake up Washington." "She's exactly who this country needs to help me fight the same old Washington politics of me first and country second," the presumptive Republican nominee said at a Dayton, Ohio, rally of about 15,000 supporters, who welcomed the surprise pick of the relatively unknown politician with cheers and flags. "She's got the grit, integrity, good sense and fierce devotion to the common good that is exactly what we need in Washington today," McCain said.
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Sen. John McCain praises Gov. Sarah Palin's "grit, integrity, good sense"
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Palin, 44, has been governor of Alaska since 2006
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Before becoming governor, Palin was mayor and council member of a small town
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Palin known for backing tough ethical standards, focus on energy, natural resources
@placeholder told the crowd, "To have been chosen brings a great challenge.