Napoli trail Roma 3-2 from the first leg after Gervinho scored the winner two minutes from time at the Stadio Olimpico.
The defeat was the second time Roma have beaten Napoli this season and Benitez believes his players must approach the game on the front foot if they are to overturn their first-leg deficit.
"To get to the final would be perfect. Roma are a tough obstacle, though," he said.
"We will play a very intense game. We have already lost twice to them this season, despite playing very well, but this time we're at home.
"I would be happy winning 1-0 but I want to do it playing attacking football."
Third-placed Napoli go into the game having completed the league double over Milan with a 3-1 win on Saturday, a result that leaves them four points off Wednesday's opponents in Serie A, having played a game more.
Despite Roma enjoying an impressive season, Benitez has belief in his Napoli side as they look to reach their second Coppa Italia final in three years.
"I have faith in my team, I don't think about Roma," he added.
"They have quality players too and are doing well, but I only think about my players and giving them confidence."