Oracle needs to win 10 more races to keep the silver trophy.
"It was fantastic racing," said Spithill, an Australian who lives in San Diego with his American wife. "We've been talking about this for a long time and there have been a lot of people who have probably bagged it and said, 'Ah, are we going to see a decent race?' Well, man, it's delivering. Just to see the energy in the crowd and the people that are getting behind us is huge. And that's making a difference. The more people who can do that, we've got a better chance of keeping the Cup here."
Team New Zealand won Race 3 earlier in the day, its third straight victory, and needs to win six more to take the Auld Mug to the Royal New Zealand Yacht Squadron, which held it from 1995-2003.
Race 4 was a thriller on a foggy, windy day on San Francisco Bay, with the foiling 72-foot catamarans sometimes veering on the edge of control.
After an even start, the boats sprinted across the bay parallel to the misty Golden Gate Bridge. Oracle skipper Jimmy Spithill got there first and swung his catamaran around the buoy at 45.97 knots, or 52.9 mph.
Oracle stayed ahead the rest of the five-leg course, but it wasn't easy.
As the fast cat approached Gate 3 at the end of the downwind leg while riding above the whitecaps on hydrofoils, someone released a daggerboard while all the weight of the seven-ton boat was on it, dropping the hulls into the water and slowing the boat from about 35 knots to 20 knots.
"It might have been the other redhead, to be honest, or it could have been me," said Spithill referring to fellow Aussie Tom Slingsby a strategist and grinder. "That was our only real crew-handling mistake, I think, since we started the regatta. The guys have been sailing the boat very, very well. It was an obvious mistake, and put us under pressure straight away. But for me, what was good to see was the guys just keeping their cool and keeping these guys behind us for the rest of the beat."
The American-based crew rounded just five seconds ahead, but slowly rebuilt its leading in a tacking duel heading upwind toward the Golden Gate Bridge.
Team New Zealand, which used good crew work to win the first three races, was a bit wobbly on the third leg. At one point its hulls popped higher than normal as if it were popping a wheelie, and the boat was a bit on edge as it rounded Gate 3 and popped onto foils.
The Kiwis closed the gap and trailed by just five seconds rounding mark four as both boats emerged from the fog. But Spithill kept Oracle ahead as the boats flew across the wind to the finish line just off Piers 27-29.
It was Team New Zealand's first real loss in this regatta. Its only previous loss came when it dropped out of Race 2 of the Louis Vuitton Cup final against Italy's Luna Rossa after an electronics problem disabled the hydraulics system that operates wing sail and daggerboards.
"It doesn't change anything for us," skipper Dean Barker said. "We certainly knew coming into this event that it was going to be very, very close. To predict that you'd make it through either way to zero, I think, would be a bit cold. We know that we've got to be on our game to keep winning races."
In Race 3, Team New Zealand skipper Dean Barker rebounded from a penalty at the first mark and overtook Oracle on the windward third leg to win by 28 seconds.
Team New Zealand's 72-foot catamaran reeled in Oracle during a tacking duel sailing upwind toward the fog-shrouded Golden Gate Bridge.
Spithill had an aggressive start and got his cat across the line first. Holding inside position at the reaching first mark, Spithill flew around the buoy and came within a few feet of Team New Zealand. Both teams flew protest flags and the Kiwis were penalized for not keeping clear. Barker had to slow down to clear the penalty.
Oracle led by 18 seconds after completing the upwind second leg. The boats headed to different sides of the course and the Kiwis began to show better speed upwind. Oracle remained in the lead the first time the boats crossed.
Halfway up the mark, Oracle let the Kiwis tack toward the left-hand boundary. Because the boundaries are new to this Cup, a boat that has tacked onto port to avoid crossing the boundary has advantage. That helped the Kiwis take control. Team New Zealand led by 29 seconds rounding the windward gate mark and kept that margin at the downwind gate before making the turn and heading to the finish.
