The 2014 governor's race should have been a slam-dunk for Anthony Brown. Larry Hogan ran a great campaign, but Brown didn't, and even in Maryland, that matters.

Republican Larry Hogan's victory in Maryland's governor's race was a stunning political upset. The businessman ran a strong campaign that was focused almost entirely on taxes and the economy. He avoided potentially divisive issues and presented himself as a non-politician in a year when voters were clearly fed up with those in power. This race would not have been close with a less appealing Republican candidate.

But that doesn't begin to explain what happened here. In 2010, Gov. Martin O'Malley crushed his Republican opponent by nearly 15 points despite a wave of GOP victories in the rest of the nation. Yet four years later, his hand-picked successor, Lt. Gov. Anthony G. Brown, lost and lost badly, despite calling on President Barack Obama, First Lady Michelle Obama and Bill and Hillary Clinton to turn out the base, and despite hundreds of thousands of dollars in attack ads from the Democratic Governor's Association. Mr. Hogan won, but just as much, Mr. Brown lost.


In 2006 and 2010, Maryland Democrats had been buoyed by Mr. O'Malley's ability to expand the party beyond the Big Three strategy of relying on big victories in Montgomery and Prince George's counties and Baltimore City that produced wins for former Gov. Parris N. Glendening and a defeat for former Lt. Gov. Kathleen Kennedy Townsend. Howard County turned from a swing jurisdiction to a reliably Democratic one. Fast-growing Charles County flipped from red to blue. And Baltimore County swung from a 66,000-vote nail in Ms. Townsend's coffin to a narrow O'Malley victory in 2010. Meanwhile, despite population loss, Mr. O'Malley actually netted more votes out of Baltimore City in 2010 than any Democrat had since William Donald Schaefer in 1986.

What this election made clear is that Mr. O'Malley's dominance in state politics was an anomaly, on the order of Schaefer's a generation before. The alignment he produced between progressives, African-American Democrats and voters with union ties now appears fragile, not inevitable. Maryland's progressives were electrified by Del. Heather Mizeur's run for governor, but many were turned off by Mr. Brown's starkly negative campaign. African-Americans mainly remained loyal to the party, but some key leaders in that community did relatively little to build enthusiasm for a man who would be the state's first black governor. And conservative Democrats abandoned Mr. Brown in droves in favor of Mr. Hogan's messages on the economy and taxes.

Ballot box victories in recent years for Maryland's version of the Dream Act and marriage equality, along with legislative accomplishments like the abolition of the death penalty and strict new gun control laws, cemented the state's status as solidly liberal, but that's not the same thing as being solidly Democratic. For generations, party identity had been paramount, but recent years have seen growth in the number of voters who are motivated by issues, not partisanship, and Mr. Brown did relatively little to reach out to this bloc other than his promise of universal pre-K.

The Brown campaign made a calculation that it could win by tearing down Mr. Hogan. But to be effective, attack ads need to play into something voters already feel about a candidate, and Mr. Hogan simply is not the radical culture warrior the Brown campaign portrayed. By the time Mr. Brown tried to pivot to positive ads at the end, it was too late in the minds of many voters.

Much of the Brown campaign's get-out-the-vote effort was focused on turning out the African-American community, which polls showed giving him their overwhelming support. The visits by the Clintons and particularly the Obamas were clearly designed with that in mind. But by most accounts, two local leaders who could have provided organizational muscle to accomplish that goal — Prince George's County Executive Rushern Baker and Baltimore Mayor Stephanie Rawlings-Blake — were unengaged.

Nowhere was the drop-off in support from Mr. O'Malley to Mr. Brown more evident than in Baltimore County's East Side, which went for Mr. Hogan in a rout. What accounts for that? Mr. Brown's race, that he hails from the Washington region or O'Malley fatigue? Perhaps, but also credit Mr. Hogan for tapping into voters' anxiety about the economy and taxes without even a hint of anti-union rhetoric.

Mr. Glendening's razor-thin victory in 1994 set off a round of soul searching among Maryland Democrats. This year's election will do the same. Conversely, after his 2010 drubbing, Mr. Ehrlich predicted that no Republican would win state-wide office in Maryland in the foreseeable future. Thankfully for Mr. Hogan, his old boss was wrong about that. Democrats may dominate Maryland politics, but their success is clearly not inevitable.