But even if both teams remain in the top three at the end of the third round-robin tomorrow, only one of them can progress to the semifinals under the Team Racing World Championship rules.
Once the boats reach the next phase of the regatta, it comes down to nations rather than individual teams - each country can only have one team in the semis.
That rule could give a much needed lifeline to defending champions, New Zealand, who have fallen off the pace in the last two days of racing to slip to the bottom half of the gold fleet.
The United States teams are in a similar predicament to the British, with one of them to be knocked out even though they are both in semifinal contention.
Leo Dixon, coach of the Great Britain 1 team, said his crew knew the drill. "It's good for team racing to get more nations in the semifinals, but it means all the best teams won't necessarily go through. That's the nature of the competition and we're all prepared for it," he said.
That doesn't mean they would hand their spot over to the other British team without a fight - the crews battle almost every weekend off the south coast of England.
Great Britain 1 captain 37-year-old Dr Hudson, formerly a top British Star-class sailor, has a determined team behind him - among them a submarine designer, an urban planner and a colonel in the British Army.
The British teams have accelerated through the ranks in the last couple of days after getting used to Auckland's shifty winds and tides on the Waitemata Harbour.
The winds calmed to a manageable 10-12 knots today on the racecourse on the edge of the American Express Viaduct Harbour, home to the America's Cup fleet.
Both Great Britain 2 and USA 2 - runner-up in the last two world championships - finished sailing today with 10 wins, while their respective national team-mates scored nine victories.
New Zealand 1 found the going tough and finished round two in fifth spot, but its not all bad news for the defending champions from the Kerikeri Yacht Club.
At the end of round robin three tomorrow, the top three nations will automatically go through to the semifinals, while the next three countries will race the top nation from the silver fleet in a repechage to find the last semifinalist.
However its likely to be bad news for New Zealand 2, from the Kohimarama Yacht Club - although it has an unbeaten record in the silver fleet it will not be eligible for the repechage.
STANDINGS ON DAY FOUR
GOLD FLEET, SECOND ROUND ROBIN:
SILVER FLEET, SECOND ROUND ROBIN: