United's manager believes supporters who have stayed loyal to the side after relegation will be a crucial element in the team's destiny this season.
But he is also is anxious to discover how his new signings cope with the pressure of playing in front of 52,000 fans during today's opening Championship match against Huddersfield Town.
Benitez said: "The fans can be anxious and we have to manage this anxiety and have the character and personality to play at the level that's needed and that people expect.
"We have to play with a Championship mentality and play really hard with the intensity that this league requires.
"It is important to realise we are a top side with a lot of fans behind us. They have to be crucial for us in a positive way, so we have to give them something."
Many of the United fans at today's clash will be waving flags provided as part of an initiative to generate more atmosphere inside St James' Park.
Benitez said:"To see 52,000 in the ground shows how important this club is to them, so we want to make sure we give them as much as we can.
"Sometimes you win, sometimes you lose, but we want to give everything to make sure we are where we want to be at the end of the season.
"Some people may say we are already up, but we are not there. We have to work very hard right to the end."