(AP) - Kirsten Gillibrand, a little-known, pro-gunDemocrat from upstate New York, has been sworn in as the state's junior U.S. senator.

Vice President Joe Biden administered the oath on Tuesday in the U.S. Capitol.

Gov. David Paterson appointed the second-term congresswoman to the Senate seat last Friday. She was named to the post after Caroline Kennedy, the presumed front-runner, withdrew from contention because of personal reasons.

Gillibrand fills a seat vacated when Sen. Hillary Rodham Clinton became secretary of state.

At 42, Gillibrand is the youngest U.S. senator. She's the 17th woman in the chamber.

Gillibrand represented a rural Republican district. She's a lawyer by trade and the mother of two young boys.To watch Gillibrand's swearing-in ceremony in its entirety, go to Channel 612 on your iO digital cable box and select iO Extra.

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