The winner of the 20-game Professional Chess Association contest must score 10.5 points, but match rules state that in the event of a 10-10 tie, Kasparov, 32, would keep his title.
It is Kasparov's fifth successful defense of the title he won in 1985.
The 18th game, scheduled for Tuesday, will decide the division of the $1.35 million prize fund, which was reduced from $1.5 million to pay for additional organizational and promotional costs.
The winner will receive $900,000 and the loser $450,000.
Playing with the white pieces, Anand, 25, of India, came close to defeating Kasparov, but the champion held on in a difficult endgame.
On move 63 , Anand was forced to trade down to a totally dead king vs. king position. With no other pieces on the board, the players agreed to a draw. Kasparov said it was difficult to play knowing he had a three-point lead and only needed a draw.
"The only way to prepare psychologically was to consider this the last game of the match and it gave me the strength to survive," Kasparov said.
Kasparov said his loss in the ninth game of the contest, which gave Anand the lead, was not his worst moment in the contest. He said that came just before the first game.
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