SAN DIEGO — The cruise vacation aboard a stricken ship is mercifully coming to an end, and an official aboard the boat said today that both passengers and crew were coping well with the “obvious challenges.”

Two tugboats were pulling the Carnival Splendor at a pace to reach San Diego Bay sometime around dawn today, almost exactly four days after the giant ship lost power with nearly 4,500 passengers and crew aboard. Coast Guard cutters will then escort the ship into San Diego’s downtown harbor.

The Coast Guard said it will rendezvous before dawn with four more tugs about eight miles off the coast and then the six vessels will gently bring the ship into port.

“It will take a lot of effort to get a 952-foot safe and secure,” said Petty Officer Rachel Polish, adding that weather conditions for the operation were favorable.

It is expected to take several hours for all passengers to get off the ship.

Cruise Director John Heald said that the people aboard “have risen to the obvious challenges and difficult conditions onboard.”