PORTLAND, Maine — Two bidders who helped drive up the online auction price of a 105-year-old, picturesque lighthouse have resolved their bidding war with a flip of a coin.

Portland real estate developer Arthur Girard and Dr. Jeffrey Florman, a neurosurgeon from Windham, flipped a coin Friday to determine which one of them would drop out of the bidding for the Ram Island Ledge Lighthouse, a 72-foot working light tower that is being auctioned by the federal government, said Girard’s business assistant, Beth Bernard.

Florman won the flip when the quarter turned up heads in the Maine Medical Center parking lot. He promptly put in a bid for $180,000. As the loser, Girard agreed to bow out of the bidding.

“They shook hands, and Art told Dr. Florman to use it in good health,” Bernard said. “Dr. Florman told him, ‘If I am the successful bidder, you’ll be my first guest to the island.’ Art feels like he lost the lighthouse but gained a friend.”

The coin flip didn’t determine who will own the lighthouse, but it removed one of the active bidders from the auction, which now is scheduled to end Monday afternoon. There’s still an anonymous bidder with an online name of “tugdocto” whose previous high bid was $160,000 and whose intentions are unknown.

Florman could not be reached for comment.

Ram Island Ledge Lighthouse was built in 1905 near the entrance to Portland Harbor. Before being automated in 1959, it was manned by lighthouse keepers who lived in isolation and used kerosene lamps and foghorns to assist mariners.

The U.S. General Services Administration is now selling it. Whoever buys it will have to maintain its historical integrity while the Coast Guard continues to operate it as a navigational aid with a flashing light and a foghorn that blares every 10 seconds.

The bidding began at $10,000 on July 9. A second bid, of $15,000, was entered on Aug. 17.

But there have been 30 bids in the past seven days, driving the price up to the current bid of $180,000. The last 21 bids — from $80,000 on up — have been made by Girard, Florman and “tugdocto.”

Girard and Florman met Thursday night after learning that they were two of the bidders. They quickly realized they had the same goals of keeping the lighthouse in the hands of a Maine owner and making sure it’s preserved, Bernard said.

Rather than continue bidding against each other, Girard suggested they flip a coin to decide who would continue bidding and who would drop out.

Nobody else had entered a higher bid by late Friday afternoon.