AUSTIN, Texas -- Sebastian Vettel is willing to shoulder his share of the blame for Ferrari's failed championship campaign this season, but also thinks his car was not fast enough at crucial parts of the year.

A miraculous turn of events would need to unfold over the remaining three races for Vettel to win the championship, with Lewis Hamilton needing just five points to put the title beyond his grasp.

Although Vettel dropped points at a number of rounds earlier in the season, his championship chances really started to unravel at the German Grand Prix in July when he crashed out of the lead of the race. Since then he has scored just one victory in Belgium and been involved in collisions at three separate races, including Sunday's U.S. Grand Prix.

Based on a conservative estimate, Vettel's errors over the course of the season have cost him at least 80 points and he currently trails Hamilton by 70 in the standings. He said he was willing to take the blame for his mistakes but maintains that Ferrari did not have the pace to win at crucial stages of the championship.

Sebastian Vettel needs to hope Lewis Hamilton scores less than five points over the remaining three races to even stand a chance of winning the title. Mark Thompson/Getty Images

"It is not like there is a fundamental problem," he said. "In the end, it looks a lot worse than it was. I have no problem admitting the mistakes I have done. On top there were some things that happened to us that didn't help us.

"The crucial bit has been that for a big part of the season, we didn't have the speed to really be there and then other stuff happens which maybe doesn't help that.

"Overall, we have the potential, but we need to still grow and learn. So there will be a lot of stuff over the winter we need to review, all of us, including myself."

Vettel said his results went into a downward spiral once he started making mistakes and losing points.

"I mean, once the s--- hit the fan, it didn't get better," he said. "There were too many of those incidents. I don't believe in luck or bad luck but surely here or there, things didn't go our way entirely."