Secretary of State William Galvin lost to Boston City Council challenger Josh Zakim at the Democratic state convention over the weekend by a margin of 55-45 percent, and no one is quite sure what to make of it.

According to the Berkshire Eagle, Zakim’s victory is the first time in 36 years that an incumbent office-holder failed to win the support of convention delegates. Pundits are scratching their heads, wondering whether the upset is related to national political trends or local dynamics. Here’s a rundown of what people are saying:

GALVIN HAS NO ONE TO BLAME BUT HIMSELF. The Boston Globe cited a series of missteps by Galvin, including an angry call to Lawrence Mayor Dan Rivera when Rivera announced he was supporting Zakim and the revelation that Galvin’s state employees were performing political tasks on government time. (Zakim’s employees at his Boston City Council office were caught doing the same thing.)

PROGRESSIVE BACKLASH. Massachusetts Democrats are angry about President Trump in Washington but can’t do much about it. So the theory is they are  taking their anger out on Galvin, a 24-year incumbent who Zakim has portrayed as being behind the times. “The Massachusetts Democratic Party estimated that 22 percent of the delegates were first-timers, and many of those newcomers since the 2014 convention were in their 20s,” said the Berkshire Eagle editorial. “They were stunned by the 2016 election results and angered by President Trump’s actions on the environment, taxes, social causes, and many other issues.”

Peter Lucas, a columnist for the Boston Herald and Lowell Sun, said Zakim catered to progressive anger by talking a lot about things that had very little to do with the secretary of state’s office, like women’s rights, being pro-choice, and standing up for immigrant rights. “It’s not just about administering an office,” Lucas quotes Zakim as saying. “It’s about leading and pushing for progressive changes.”

In the current environment, and particularly at a state Democratic convention in a very blue state, Galvin was at a disadvantage. “I don’t think there’s patience with this old way of doing things anymore,” said Maurice Cunningham, a political science professor at the University of Massachusetts Boston. “He is just another old white guy to be pushed aside,” Lucas said of Galvin.

THE WALSH FACTOR. It’s one thing for US Rep. Seth Moulton to back Zakim, who, like Moulton did, is taking on an incumbent. But why is Boston Mayor Marty Walsh getting involved? Even though Walsh did not attend the state convention, there were widespread press reports that the mayor urged delegates from Boston to back Zakim. Walsh’s motives are unclear. He had no problem backing incumbent congressman Michael Capuano over Boston City Councilor Ayanna Pressley, but for some reason he apparently prefers Zakim to Galvin. Could Walsh be delivering a little payback for Galvin’s opposition to the height of the proposed Millennium Partners tower at Winthrop Square, a controversial real estate project that paid big dividends for the city?

THE NAME GAME. Lucas says Galvin is facing the same challenge that former attorney general Edward McCormack was confronted with in 1962 when he ran for the US Senate against Edward M. Kennedy. Kennedy had no resume at the time, but voters loved his last name so he won and McCormack lost. The name Zakim doesn’t have quite the cachet as Kennedy, but Lucas points out that the Zakim Bridge is named after the city councilor’s famous father, Leonard Zakim. “Everybody has heard of the Zakim Bridge. Not everybody has heard of Billy Galvin,” Lucas said. “To drive home the connection, Zakim has termed his candidacy as a ‘bridge to progress.’ Get it? His campaign literature has an image of the iconic bridge on it.

Now Galvin finds himself not only running against a man, but running against a bridge as well.”

AGE MATTERS. Galvin is 67, nearly twice the age of Zakim, who is 34. Some voters may just think it’s time for a change.