Washington (CNN) – Republicans might not have to wait until the next Congress to pick up seats on Capitol Hill.
Due to certain states' election laws, three Senators who were appointed to their seats this year will have their terms end after the November 2 midterm elections. Illinois, Delaware, and West Virginia are all holding special elections this November, and none of the appointed Senators currently holding those seats are on the ballots.
Republican wins in any of these races could weaken the Democrats' 59-seat majority in the Senate if the current session of Congress continues past Election Day or is re-convened before the new 112th session is sworn in this January.
Currently, the Senate will reconvene on Sept. 13, and is expected to remain in session at least through the month but the end of the session is contingent on legislative negotiations still underway.
In Illinois, two Senate races will appear on the ballot this November – one for a special election to fill the seat for the remainder of the current Congress, and another for a full six-year term.
The seat is currently held by Democrat Sen. Roland Burris, who was appointed by former Gov. Rod Blagojevich to finish out the last two years of President Obama's Senate term. However, federal judges later ruled that the appointment only lasted until November 2, and a special election was scheduled.
Burris's tenure as Senator has been marked by controversy. The Senate Ethics Committee issued a letter last November admonishing Burris "for actions and statements reflecting unfavorably upon the Senate" in connection with his controversial appointment by the embattled Blagojevich. Burris announced in July that he would not run for a full term.
Illinois State Treasurer Alexi Giannoulias, a Democrat, and five-term Republican Rep. Mark Kirk are locked in a tight battle for the seat for both special and full terms.
The winner of the special election is expected to be certified shortly before Thanksgiving, according to an Illinois State Board of Elections official.
Delaware is also holding a special election in November to determine who will serve the remaining four years of Vice President Joe Biden's Senate term.
Sen. Ted Kaufman, Biden's former chief of staff, was appointed to replace Biden after he became Vice President.
Many consider Delaware a prime potential pick-up for the GOP this November. The Republican primary, set for Sept. 14, has drawn national attention in recent weeks as the moderate Rep. Mike Castle seeks to stave off an upset by Tea Party-favorite Christine O'Donnell. The winner of the primary will face Democrat Chris Coons in November. The Delaware State Board of Elections will certify the winner of the special election on November 4, clearing the way for a new Senator to be sworn as early as mid November.
Sen. Carte Goodwin of West Virginia became the Senate's 59th Democrat early this year after the death of long-time Senator Robert C. Byrd. Gov. Joe Manchin appointed Goodwin to fill the seat until the special election, which will also be held on November 2.
Manchin, a popular two-term Democratic governor, decided to run for the seat himself, and easily won a special primary this August. He now faces Republican businessman John Raese in the special election. The winner of that election is expected to be certified by mid November, and will serve the remainder of Byrd's term.