Ricciardo and Vettel are respectively 60 and 117 points behind leader Lewis Hamilton with 150 still available.
Red Bull team principal Christian Horner said their title hopes were a "long shot" but Mercedes' reliability problems gave them a chance.
"Due to their shocking reliability, hopefully we can keep ourselves in the championship," he said.
Although reigning champion Vettel is almost completely out of the reckoning and has only a mathematical chance, Horner says it is too early for Red Bull to consider team orders to aid Ricciardo's challenge.
Vettel finished second to Hamilton in Singapore on Sunday with Ricciardo third while Nico Rosberg retired with an electrical failure.
"Mercedes have an enormous advantage at this point," Horner said. "We'll take it one race at a time. Both of them are still just in it and both have taken a chunk of points out of Nico.
"Daniel, OK he's conceded three points to Seb but is that going to make the difference? Impossible to say with a crystal ball at this stage but at the moment it doesn't make sense to interfere with team orders.
"Daniel is totally comfortable and happy with that.
"If there was a realistic chance of Daniel winning and Sebastian was mathematically out of the championship, then we'd do the best we can for the team but the situation we're in at the moment is it's a long shot."
Red Bull insist Daniel Ricciardo and Sebastian Vettel are still in the fight for the drivers' championship.