Benitez's team beat Huddersfield Town 3-1 at the John Smith's Stadium tonight thanks to goals from Matt Ritchie, Daryl Murphy and Dwight Gayle.
Newcastle are now 11 points clear of third-placed Huddersfield, though David Wagner's side have a game in hand.
The victory followed Tuesday night's 2-1 success over second-placed Brighton and Hove Albion, beaten 3-0 by Nottingham Forest this afternoon.
“We knew that it was a difficult week against very tough teams," said United manager Benitez.
"Brighton and Huddersfield are tough teams and they were in form. They rested players for this game. I am really pleased with the performance of this team.
“We knew they were dangerous going forward. That they can move the ball from one side to the other. We had to focus on the defensive side. We had to win the second balls and that was the key."
However, Benitez – whose side take on Reading at the Madejski Stadium on Tuesday night – insists Newcastle's lead is NOT a comfortable one.
“We know Huddersfield have game in hand," he said. "That could be eight (points). It is so difficult in this division.
"We have to make sure we will be ready and get three points, then after we can see what the difference is. We just have to focus on the next game."