From CNN's Donn Cost
(CNN) - (CNN) - Democrats are keeping their eyes on a filibuster-proof Senate majority of 60 seats in Tuesday's elections.
The party picked up one seat early in the evening with the projected winner of Virginia's open Senate seat, Democratic former Gov. Mark Warner. Warner will fill the seat of retiring Sen. John Warner, a Republican. The two Warners are not related.
According to CNN's projections, six Democrats have kept their seats. They are Sen. Mark Pryor of Arkansas, vice presidential candidate Sen. Joe Biden of Delaware, Sen. Dick Durbin of Illinois, Sen. John Kerry of Massachusetts, Sen. Frank Lautenberg of New Jersey and Sen. Jay Rockefeller of West Virginia. If Biden is elected vice president, he'll give up his Senate seat, and the state's Democratic governor would appoint a replacement.
So far, four Republicans have held their seats. They are Sen. Susan Collins of Maine, Sen. James Inhofe of Oklahoma, Sen. Lindsey Graham of South Carolina - John McCain's chief ally in the Senate - and Sen. Lamar Alexander of Tennessee.