Washington (CNN) - While the vast majority of newly elected congressional lawmakers don't take office until early January, two actually get sworn in Monday.
Less than two weeks since their victories in the midterm elections, Delaware's Chris Coons and West Virginia's Joe Manchin, both Democrats, will become the newest members of the Senate, when Vice President Joe Biden swears them Monday afternoon.
Manchin, West Virginia's popular two-term governor, won a special election to fill the final two years of the term of the late Democratic Sen. Robert Byrd, who held the seat since 1959. Manchin, who defeated Republican Senate nominee John Raese, is considered a conservative Democrat. He was backed by the National Rifle Association and the Chamber of Commerce in his bid for the Senate.
In July, following Byrd's death, Manchin named attorney and political confidante Carte Goodwin to temporarily fill the seat.
Coons, Delaware's New Castle county executive, will be filling out the final four years of Biden's old term in the Senate. Biden, who served in the Senate for nearly four decades, stepped down from his seat after his election in November 2008 as vice president. Former Biden aide Ted Kaufman was named as an interim replacement, and did not seek a full term.
Coons easily defeated conservative commentator Christine O'Donnell in a special election that grabbed national headlines thanks to many of O'Donnell's past controversial comments. O'Donnell, who was backed by Tea Party activists and Sarah Palin, upset longtime moderate Republican Rep. Mike Castle, a former two-term governor, in the GOP primary.
The swearing in of both Coons and Manchin does not change the balance of power in the Senate, which currently stands at 59 (57 Democrats plus two independent senators who caucus with the Democrats) Democrats to 41 Republicans. The Democrats will have a smaller 53 to 47 majority starting next year.
Two other special elections for the Senate were held on Election Day. In Colorado, Democratic Sen. Michael Bennet won a full six year term. He was appointed to the seat early last year, after Democratic Sen. Ken Salazar stepped down to become Interior Secretary in President Obama's administration.
And Republican Rep. Mark Kirk of Illinois won a special election to fill the final weeks of Obama's old term in the Senate, as well as a full six year term in office. Kirk will succeed Sen. Roland Burris, a Democrat who was named early last year to the Senate by then embattled Gov. Rod Blagojevich, who was subsequently ousted from office.
Kirk will be sworn in later this month.
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