McLaren racing director Eric Boullier says his team has to believe that they can stand on top of the podium once again in 2014.
McLaren left the first round of the season in the lead of the constructors' championship but failed to score points in Bahrain or in China, with both Jenson Button and Kevin Magnussen finishing outside of the top 10 last weekend.
McLaren has not won a race since the end of the 2012 season.
"We have to believe we will win a race," he told a McLaren teleconference. "I think we will be able to keep pushing to bring a very strong and aggressive development for the season. I think we put ourselves in a position to fight for a win - maybe not in the first part of the season, but hopefully later.
"If you look in detail obviously it looks like we have stepped back from the beginning of the season. I made clear that a lack of downforce was obviously hurting us when you have very hot or cold temperatures, and there is a technical reason for that. It is true that Australia was a bit optimistic, but we also prepare ourselves to pick up points or even podiums from the others.
"2014 should be a benchmark year for us. It should be seen as a year of rebuilding a winning team."
McLaren remains without a title sponsor after the departure of Vodafone at the end of 2013 and a different sponsor has appeared on the sidepods and rear wing of the MP4-29 at every event so far in 2014.
Boullier insists that McLaren boss Ron Dennis is still negotiating in this department.
"The plan Ron discussed is happening," Boullier said. "Until we have signed the package, signed the final contract, obviously nothing will be announced. Until we are in a position to do so, we will keep going as we are now."