The Gunners went in front when Andrey Arshavin prodded in after 14 minutes but Jimmy Bullard levelled with a penalty after 28 minutes following a clumsy Sol Campbell challenge on Jan Vennegoor of Hesselink.
The visitors struggled to break down Hull following the 45th-minute dismissal of George Boateng but their persistence paid off when Bendtner netted the rebound after Boaz Myhill only palmed out Denilson's shot.
"It's maybe not good for my heart, but for the championship it's not bad," Wenger said after Arsenal's fifth straight win.
"We have eight games to go, we are in there, why should we not believe?
"What I believe especially is that we will give absolutely everything to do it. You saw that in the game today. We were a bit jaded but we kept going.
"We needed the three points and we got it after the 90 minutes."
Wenger had no complaints about the penalty, but did not feel Campbell's challenge was worthy of a red card as the last defender.
"Vennegoor of Hesselink played him in an intelligent way," added the Gunners boss.
"Sol had no other option than to touch him but there was no intention, it was accidental.
"And he (Vennegoor of Hesselink) was offside at the start."
Hull manager Phil Brown felt Campbell - a player he spoke to over a move to the KC Stadium last summer - should have been sent off.
"The pivotal moment was undoubtedly in favour of Arsenal," Brown said. "He should have been red carded, it's as simple as that.
"It was offside, but it wasn't offside because the flag didn't go up.
"He's denied a goalscoring opportunity and under the letter of the law, he should have been red carded."
After a difficult week in which Bullard and Nick Barmby were involved in an altercation in front of members of the Women's Institute near the Humber Bridge, Brown was delighted with the attitude of his side.
He added: "I apologised to the Women's Institute during the week for the fighting spirit we showed unfortunately in public, I won't apologise for the fighting spirit shown today."
Brown also defended Myhill for his error and Boateng following his dismissal.
"Boaz Myhill has done a fantastic job at this football club," he said.
"Yes, he'll get judged on the way the ball came off him and George Boateng will get judged on the fact he got a red card.
"But these players can hold their heads up high because of the determination and the pride in the performance they put in.
"I'm very proud of my players. Ten men have harried and chased one of the best footballing teams in the country, if not in Europe, if not in the world."
Meanwhile, Brown faces an anxious wait to discover Kamil Zayatte's fate.
Zayatte was on crutches following the match after being forced off early in the second half following a strong challenge by Campbell.