"I think it's going to end up being a closer run thing. It is a big advantage that they have now [but] time will certainly tell," he said. "In the end it may well come down to just a few hours between the east and west option but really we're going to have a better idea in the next 24 hours."
There are another two boats ahead of Camper to the west - American team Puma and Spaniards Telefonica - but the New Zealand entry closed in to trail them by only 36 and 32 nautical miles, respectively.
Beyond Cape Verde is a vast windless zone known as the Doldrums, an area Groupama will have to head west to avoid, meaning the split in the field may soon close up.
The fleet is down to four boats as it heads to Cape Town, after Abu Dhabi became the second team to pull out because of damage to the yacht. Along with Chinese team Sanya, Abu Dhabi will now aim to have their boat ready for in-port racing on December 10, before the second leg gets underway the next day.
The race, in its 11th edition, began with a smaller than usual fleet because of the current financial crisis, with many teams unable to commit to such costly campaigns.