Bent has netted five times in the Premier League this season out of a total of seven goals for the Black Cats.
Asamoah Gyan is the only other player to have hit the target in the league, with Sunderland's seventh goal coming from Birmingham defender Stephen Carr at the wrong end.
Welbeck, who moved to the Stadium of Light on loan from Manchester United over the summer, has not yet opened his account for his new club.
He admits there has been a reliance on Bent but is confident Sunderland will soon start to fire in attack with more players contributing goals.
"We have to get better at playing that final pass and showing a killer instinct in front of goal," said Welbeck.
"We can't keep relying on Darren to score goals. Everyone has to chip in.
"I think it will click soon and when it does we'll start getting a few goals."