The sixth-largest jackpot in the Mega Millions lottery's 14 1/2-year history, an estimated $312 million, is on the line for Friday's night drawing.
A ticket with all six numbers has not been sold since the Feb. 1 draw, 14 draws ago.
Tickets will be sold until 7:45 p.m. The draw will be held just before 8 p.m.
The odds of matching all five numbers and the Mega number are 1 in 175,711,536, according to the Mega Millions Web site.
The jackpot would increase if ticket sales are heavier than expected.
The jackpot is the largest since Jan. 4 when it reached $380 million, the second largest in the history of the game that began on Aug. 31, 1996 and was known as the Big Game with six states participating.
The Mega Millions game is now played in 41 states and the District of Columbia. The largest jackpot, $390 million, was reached in the March 6, 2007 draw.
Buying tickets at a store where winning tickets have been sold in the past will not increase a purchaser's chance of winning a jackpot, according to USC mathematics professor Ken Alexander.
"The chance that a given place will sell a winning lottery ticket is just related to how many tickets they sell," Alexander said.
