Democrat Sen. Mark Kelly from the U.S. state of Arizona was reelected in the Nov. 8 midterm elections, according to a projection Friday by The Associated Press.
The result gave the Democrats and Republicans 49 seats apiece in the 100-seat chamber.
Results in the Senate race in neighboring Nevada have yet to be released. Given the Republican candidate's lead in that race, the balance in the chamber might settle at 50 to 49.
In Georgia, on the other hand, where balance in that state's Senate is at stake, it may not be known who has the majority until a second round of voting is completed Dec. 6.
If Republicans win in Georgia, they will have enough seats to secure a majority in the chamber.
But the Senate will be evenly divided if the Democratic candidate in Georgia wins. In that scenario, U.S. Vice President and Democrat Kamala Harris will tip the scales in favor of the Democrats, maintaining their majority in the Senate.
The full 435 seats in the House of Representatives and 35 seats in the Senate were up for election Nov. 8.
