Madrid closed the gap on Barcelona and Atletico Madrid at the top of the table to three points with a 1-0 win over Espanyol on Sunday, a result that took them to 47 points at the halfway stage in the campaign after their rivals shared a goalless draw.
Italian coach Ancelotti saw Pepe head home his third goal of the season to take the three points, and he believes whichever team achieves a three-figure points tally will claim the top-flight crown.
"It's not normal but this is the Spanish League where there are three very strong teams," he said.
"We've said it before; 100 points is what it will take and we need to get them. It will not be easy but we have excitement and enthusiasm.
"It was an important moment because Atletico and Barcelona are doing well and there are not many chances to cut the gap. We have to be satisfied."
Madrid struggled to break down their opponents at Estadi Cornella-El Prat but did see Cristiano Ronaldo and Karim Benzema waste good chances to add to their tally.
Ancelotti, however, was impressed by his side's display and revealed he had persuaded Pepe to remain at the club during the close-season.
"I'm satisfied with the game as the team has balance, played good football and has not taken risks," he added. "We cut the points (to the top two) and that was the objective.
"Everything has gone well. We started the game slowly and suffered in the first 15 minutes but after that we had many opportunities. After the goal we controlled the game well.
"I think Pepe is having a very good season. At the beginning he was hesitant about staying but decided to after I told him he was important."
