The Azzurri are trailing by one goal to the 2011 winners in Thursday night's Europa League last-16 showdown, thanks to a Jackson Martinez goal in Porto's first leg, but they have won all four of their home games in European competition this season.
Napoli were desperately unlucky to miss out on the knockout stages of the Champions League having won all three games on home turf - and another in Marseille.
Borussia Dortmund and Arsenal also finished with 12 points and progressed thanks to superior goal difference.
British hopefuls Swansea offered little resistance in the cauldron of the San Paolo in the last 32 of the Europa League and, despite Porto's European pedigree, Napoli head coach Benitez believes the Dragons can be cowed into submission by his vociferous home support.
He told sscnapoli.it: "So far in Europe we have demonstrated we have the ability to play well and express ourselves against the big clubs, especially at the San Paolo.
"We did well in the Champions League and against Swansea in the last round.
"Our fans' support is crucial and could be decisive tomorrow."
A Champions League-winning coach with Liverpool, Benitez guided Chelsea to Europa League glory in Amsterdam last season, and claimed the UEFA Cup with Valencia in 2004.
Despite the fact his dedication to the tournament has drawn disparaging comments from his successor at Stamford Bridge, Jose Mourinho, the Spaniard maintains chasing Europe's second trophy is a worthy undertaking.
"We are very excited because our goal is to keep making progress in Europe," he added. "It's a great showcase for the team and is helping to improve the club.
"It's a competition we hold in high esteem and we will do our utmost to progress tomorrow."
The season is over for goalkeeper Rafael Cabral (anterior cruciate ligament), while wing-back Christian Maggio is recovering from emergency surgery on a pneumothorax he suffered in the first leg.
Porto keeper Helton will miss at least three months of action after rupturing his Achilles tendon against Sporting at the weekend - he has since undergone successful surgery - while Alex Sandro serves a one-match ban.
Abdoulaye Ba might have filled in for the left-back but he is cup-tied having already played for Vitoria Guimaraes in this year's competition.
Visiting coach Luis Castro has therefore named Kadu, Maicon, Mikel Agu, Josue and Kelvin in his matchday squad.
The interim boss, who replaced Paulo Fonseca two weeks ago, told his pre-match press conference: "We go into the second leg following a positive result, although we could have scored more goals to win by more than 1-0.
"Despite having a few injuries we are optimistic we can go out on to the pitch and give our all to reach the next round.
"That is our goal."