Sauber has not made a development push to try and catch Mercedes for fifth in the constructors' championship because it believes it can do the job just by 'getting its act together'.
With Mercedes having not scored at all since September's Singapore Grand Prix, Sauber has closed to within 12 points of taking a top-five Formula 1 championship place for only the third time as an independent constructor.
Sauber has now secured four podium finishes in 2012 compared to Mercedes' three, the last of which came back in June in the European GP.
Asked by AUTOSPORT if she now felt overhauling Mercedes was achievable in the remaining two races, Sauber team boss Monisha Kaltenborn replied: "It is, but it's very tough. And we fully aware of that."
She is sure Sauber's current package is quick enough to beat Mercedes provided the team delivers its potential in America and Brazil.
"This is about optimising things. It's not about developing anything," said Kaltenborn.
"We know that we have a competitive car.
"If we get our act together during a race weekend, especially during the race but also in qualifying to start with, things can look good.
"But we are fighting against a very good team, so it's going to be very tough."
While McLaren-bound Sergio Perez scored Sauber's first three podiums of the season, his team-mate Kamui Kobayashi has the better recent results, including a podium in Japan and sixth place in Abu Dhabi. Perez has been embroiled in a string of incidents over the same period.
Kobayashi's F1 future is currently in jeopardy, with Nico Hulkenberg confirmed for one Sauber seat next season and GP2 graduate Esteban Gutierrez tipped for the other.
Kaltenborn underlined that a range of factors would decide Kobayashi's fate, and that the team would not be swayed by one-off results.
"We have never said that we are making his future dependent on single occasions, in either direction - good or bad," she said.