Ainslie is the first Briton to experience victory at the event since Charlie Barr led the American team Columbia to three consecutive victories in 1899, 1901 and 1903.
The champagne was in full flow by the time Oracle made it back to dry land with fans in raptures at the side of the port.
"It really is all about the team," added Spithill. "On your own you're nothing, the team make you look great.
"I'm so proud of the boys. We were staring down the barrel at 8-1 but the boys didn't even flinch. It was a fantastic team effort."
Team New Zealand skipper Dean Barker was left inconsolable at the conclusion of the titanic tussle.
He added: "I'm incredibly proud of the team and what they've achieved but gutted we didn't get the last win we needed to take the cup back to New Zealand.
"It's hard to swallow."