As Democrats prepare to meet in Chicago this week, I thought back to their tumultuous 1968 convention, the third of 27 I covered.

I cost the Democrats the presidency. At least that’s what the press secretary of this year’s defeated Democratic candidate told me.

Let me explain.

As a junior member of the AP Congressional staff, I was assigned to wait outside the suite of presidential candidate Vice President Hubert Humphrey while he finalized his choice of running mate. At one point, Press Secretary Norman Sherman came out and announced that Humphrey was still consulting with Democratic leaders about his choice.

Was Lyndon Johnson among these politicians? I asked innocently. The unpopular president was sulking on his ranch in Texas and was unwelcome in Chicago after splitting the party and withdrawing from the race.

“Lyndon who?” Sherman replied, always a man with a quick mind, sometimes too quick. Quickly realizing his faux pas, he added, “That’s confidential.”

I looked at the three dozen or so reporters in the crowded corridor and quickly realized that there was no way I could comply with Sherman’s late request, especially after I had burned my fingers two weeks earlier on another confidential matter involving Humphrey.

When I got to a phone, I dictated the exchange and then continued to wait. Eventually, Humphrey chose Maine Senator Edmund Muskie, offering a glimmer of hope for a convention marked by bitterness in the hall and clashes between police and anti-war protesters outside.

But that was just the beginning. My AP colleague Harry Kelly had, without my knowledge, informed Sherman that I was going to publish his scathing commentary. That meant wide distribution, because at the time the AP wire was the closest thing to the modern Internet.

All hell broke loose at the Johnson ranch, as I learned years later when Sherman told the incident to Todd Purdum, who was writing a book about the Civil Rights Act of 1964.

“A Secret Service agent came up to me and said there was a call from ‘THE RANCH’ at their command center,” Sherman said. Both Johnson’s press secretary George Christian and his deputy Loyd (CQ) Hackler were on the phone, and “when I said hello, they called out ‘Norman, who?’ We laughed and soon hung up.”

Humphrey’s reaction was less friendly. The vice president, according to Sherman, looked at him and “growled: ‘Did some son of a bitch on our staff ask, ‘Who is Lyndon?'”

“You have the right son of a bitch, but the wrong line,” Sherman said he replied. “I said, ‘Lyndon who?'”

Sherman later discovered that Arthur Krim, a movie producer and Humphrey’s primary fundraiser, had called him from the Johnson ranch and said he wouldn’t raise another penny “if he had people like me on the team.”

For years afterward, Sherman regularly, but jokingly, blamed me for Humphrey’s loss of the election, claiming that was the reason Johnson had remained inactive for weeks. In fact, he complained about Humphrey’s departure from his Vietnam policy, and Humphrey lost the election due to intra-party disagreements.

A footnote: A few years later, my son Carl went to work at a brokerage firm in Bethesda, Maryland. One of his colleagues there was Sherman’s wife, Ginny. When she found out his name, she immediately told him that his father had cost Humphrey the 1968 election.

The “Lyndon who?” incident was just one of several memorable events that stuck in my mind from Chicago, where I was fortunate to be covering politics rather than the daily clashes on the streets.

It was the only presidential debate of the year, with Humphrey, Minnesota Senator Eugene McCarthy, and South Dakota Senator George McGovern clashing before the California delegation.

Another reason was unrest in the convention’s Rules Committee, which had long-term effects. A battle on the floor, which the insurgents won, led to the creation of the McGovern Commission, which overhauled the party’s nomination procedures to the point that most states introduced primaries and eliminated insider-controlled conventions.

The Rules Committee met on an upper floor of the Conrad Hilton Hotel, and I soon noticed that there were only two pay phones nearby. This was long before cell phones and a strike by the local telephone company meant that the usual extra phones could not be installed at meeting locations.

I was determined to make sure no one beat me to the punch with my version of the story. I remembered that an AP colleague, Austin Scott, later at the Washington Post, had shown me how to disable a pay phone by unscrewing the mouthpiece and turning over a part called the diaphragm.

So that’s what I did, so I’d always have a phone handy when I needed one. Many tried to use the tampered phone without success, including Illinois Governor Sam Shapiro, the committee chairman. “I don’t think it works,” I told him helpfully.

But it always worked for me. At one point I called my editor and was told that the New York Times had questioned my last update because they had not heard anything similar from their correspondent.

“Maybe he’s having trouble finding a phone,” I said.

Democrats were so disappointed by the convention that they avoided Chicago for the next 28 years. The 1996 convention, which re-nominated President Bill Clinton, went smoothly and is remembered for the frequent singing of the “Macarena,” a popular summer song by delegates.

Now they’re returning to Chicago, hoping for a convention that looks more like 1996 than 1968. I won’t be there, but I’ll be watching, and I bet a nonagenarian from Iowa named Norman Sherman will be there, too.

Humphrey died a decade later without ever becoming president. But we’re both still here, laughing about it.