Lotus insisted on Saturday that their plans for 2014 remain on track despite apparent delays to a widely-expected investment in the team by the Quantum consortium.
Team boss Eric Boullier, who saw much-improved Frenchman Romain Grosjean take sixth place on the grid for Sunday's Brazilian Grand Prix, said he still believed the deal will happen.
He said: "There is still some discussion ongoing and now between bankers. The process is not fully completed, but I think part of it has been done which is a good sign We hope obviously that everything is closed by early next week."
The deal may decide the identity of Grosjean's team-mate next season.
Nico Hulkenberg, currently with Sauber, who qualified 10th, has been linked with the seat for several months, but may face a challenge from heavily sponsored Venezuelan Pastor Maldonado, released by Williams.
Maldonado has a reported 35 million euros sponsorship deal to support his hopes of bagging the drive.
Finn Heikki Kovalainen, who has been standing in for injured compatriot Kimi Raikkonen, has also been named as a possible contender.
He qualified 11th in Saturday's rain-swept session.
Talks are between the international consortium backed by investors in the United States and the Middle East and the Lotus owners.
Boullier added: "You need to have the right package to get the right driver, but sometimes maybe the right driver is with the right package," he said.
"We will do our best to keep our thoughts all together. That is the main point, making sure the team is sticking together and the basic ingredients are on board - to deliver the best package we can.
"I am still confident I will get one of the guys I want."
For Boullier and Lotus, Grosjean's surge in form and composure has been the highlight of the season as he emerged as the most improved driver on the grid.
Asked for an explanation for his run of form and points, he admitted that becoming a father had helped him mature and gave credit also to the work of a psychologist.
"I knew I was capable," he explained. "We have a good car and a good team. It just works. It's not a secret. That's what we have been trying to achieve every weekend."
As to his engagement with a psychologist, he added: "I think it has made a huge difference. I knew I was quick and capable of winning the title. I just needed to put things together. It has made me a better man and a better driver."
And on driving around Interlagos in treacherous conditions, he said: "It's certainly a challenge with the spray and standing water, but despite this it's still awesome to be driving around Interlagos."