The 28-year-old has been in inspired form for the Cottagers this season and scored two hat-tricks this month, including a treble in the 5-2 defeat of Newcastle last weekend.
Fulham face Everton on Friday night in the FA Cup fourth round, where Dempsey will face fellow United States internationals Landon Donovan and Tim Howard.
The latter suggested in the build-up to the match that the west Londoners are increasingly relying on Dempsey's presence, although Jol downplayed the comment.
"It is always great to have players that can make the difference and he (Howard) probably does that for Everton as well," the Dutchman said.
"You always rely on good goalkeepers, good centre forwards and productive players.
"You will never be a good team without one or two players [that can make the difference].
"Even Barcelona would not be without players that can make the difference and Clint did that.
"We have other players that can score. We have got goals in us, with Bryan Ruiz, Mousa Dembele and Bobby Zamora, who was involved in at least three goals the other day.
"We have got the quality but I can't deny that Clint was very different for us this year.
"Maybe he was in the past. I think so because he was our top scorer before.
"You always like your top scorer to be up front but if it's Clint, it's Clint. If it is Bobby, it is Bobby. It doesn't matter to me."
Dempsey's form has seen him attract reported interest from other clubs but Jol insists he does not expect him to leave Crave Cottage anytime soon.
"You don't have to hang on to players when they have longer-term contracts," he said.
"You only try to hold onto players who contracts have finished and then try to do something.
"With Clint there is no issue as he has two years to go.
"We certainly are not encouraging bids because we want to keep what we have got."
Jol also once again rejected speculation linking Zamora and Andrew Johnson with a move but, while keen to keep his squad intact, admitted he would be willing to let fringe players Rafik Halliche and Bjorn Helge Riise leave.
"With Halliche he is probably our fifth centre-back so he is in a difficult position," he said.
"I feel for him because he played for the reserves when we beat Arsenal and played a terrific match.
"He is a good player but I can't play five centre-backs. If there is a good opportunity for him, I would like to help him.
"Bjorn was at Portsmouth and came back so we have to wait and see.
"The boy needs to play but I have to find a good club for him that play in a certain style.
"They have to guarantee or promise me that he will be a good part of the squad because otherwise he will stay here."
Aside from drafting in a couple of players for the youth team, Fulham have yet to do any major transfer business this month.
Jol believes it is "quieter than ever before in England" and revealed a potential move for Catania striker Maxi Lopez looks to be over.
"We said we would like to do something on loan with one or two players," he added.
"Catania were probably not in a situation to put Maxi Lopez, who is a good player and scored some goals for them, on loan.
"I don't think he will go anywhere else on loan. If is a non-starter."