The natural impulse, surveying 20 years of Nashville politics, is to compare snapshots two decades apart. Then: a mayor from East Nashville who went to MTSU and is remembered for a television appearance with his country-singer fiancée (while still married to his third wife) to play some harmonica and chat up Phil Donahue about what Time magazine labeled Hizzoner's "spectacular sexual escapades." Now: a mayor who grew up in Massachusetts, went to Columbia and Vanderbilt Law, reads on a Kindle, and roots for the Boston Red Sox.

One could read into the contrast between Bill Boner (c. 1989) and Karl Dean (c. 2009) a city's political evolution from hick to hip, from embarrassing to enlightened, from corn to cosmopolitan. That would be tempting, but it would also be misleading—an oversimplification of what has and what decidedly hasn't changed in the city's political landscape.

When Phil Bredesen was elected mayor in 1991, it felt like a critical moment. Slowly dying were the days of hardball ward politics—the fiefdom of the late Sheriff Fate Thomas, he whose ring had to be kissed by those aspiring to city office. After three straight homegrown mayors, we turned the courthouse over to a rich guy from Up North with business chops and a penchant for government by spreadsheet, and without the deep connections to entrenched social networks that had defined Nashville's political leadership since Metro government came to be in the 1960s.

As the first of three consecutive mayors with Yankee roots and no personal ties to Nashville's municipal history, Bredesen's arrival was a palpable turning point. And sure enough, Nashville is in many ways a more economically and culturally evolved place to live and work than it was 20 years ago. But the trajectory of the city's political life isn't quite so linear. It's a more complex blend of change and stability—of evolution and stagnation.

Political change in Nashville over two decades starts with geography. Before Bredesen, a successful citywide race was apt to involve coalitions of working-class support north and east of the river. (The previous two mayors, Boner and Richard Fulton, were graduates of East High School.) Business leaders had always quietly funded and promoted viable campaigns, but the road to precinct organizing and voter turnout went through Thomas, who ultimately did hard time for corruption. After Bredesen, electoral wins started to swing on support south and west.

The city's captains of commerce still push agendas and candidates, to be sure, just in a less covert and monolithic way. Today we have no "Watauga," that small cabal of boardroom and law-firm bigwigs who met in secret until the 1980s to hatch projects, both civic and electoral. Watauga didn't run the city, but as Bruce Dobie wrote here in 2002, it "pulled the city's strings" by putting into play "a vision of the things that needed to happen," be they downtown development or integration.

With the death two weeks ago of business titan and Watauga principal Nelson Andrews, close on the heels of Watauga minute keeper and former Banner editor Eddie Jones, the door officially closed on an era of enlightened puppet mastery. The Chamber of Commerce still flexes its muscle whenever possible, but Nashville's business elite is now a generation removed from the can-do World War II vets and local boys who sought to reshape their city.

The role of unions has also changed. Uniform labor support for a candidate once meant likely victory. While unions are still important sources of campaign funding and energy, their political influence has markedly waned (see Karl Dean's 2007 mayoral win over labor-backed opponent Bob Clement). The culprit is a diluted local base of organized labor—a decline in private-sector unionism that hews to national trends, along with the elimination some years ago of the requirement that Metro workers live in the county.

Since the 1980s, there have been two important changes in municipal governing. One is term limits, enacted in the 1990s and confining Metro Council members to two four-year stints. (Full disclosure: My wife currently serves on the council.) The inevitable result is more frequent transfusions of new blood, at the expense of institutional memory and experience-honed expertise on complex issues.

The other change is creeping expansion of government by referendum. Over the years Nashvillians have gone to the polls to alter public employee pay plans, switch to an elected school board, finance a pro football stadium, and, most recently, reject the English-only silliness. Perhaps most consequential is the 2006 vote to bar future property tax increases without ballot approval. Karl Dean has yet to ask voters for a tax hike, but tight budgets and a stagnant economy may soon force his hand.

These changes to political process have eroded Metro Council's already limited ability to guide the city's agenda. Given an oversized part-time council with minimal resources and without political party structures, it is both difficult and politically risky to challenge a mayor who can control civic discourse with the help of a sizable budget and professional staff. As one former council member put it, "Council members are so afraid now that the mayor does not have to give anything to get his way."

Last, but far from least, are momentous changes in the news media that cover it all. Aggressive, competitive journalism has given way to a feckless audience-driven chain daily that mostly sucks up to political power, a hybrid online/offline quasi-daily without an editorial voice, a chain alt-weekly fighting to reinvent its demographic, and TV news operations that traffic mainly in crime, sports and fancy weather gadgetry (albeit with less puppetry). Bloggers have taken up some of the slack, but online independent media are substantially less developed and influential here than in many other cities.

Yet for all of these forces transforming Nashville's political culture and landscape, there's an awful lot that hasn't really changed. We still have powerful mayors who frame the act of governing in terms of pinning their legacies on a few big things: a convention center and a sewer system (Fulton), an airport expansion (Boner), a stadium, arena and library (Bredesen), neighborhoods and the courthouse (Purcell), and—coming full circle—another convention center (Dean).

We still have mayors who treat the Metro Council as an inconvenient obstacle rather than a constructive counterweight, and we still have a Metro Charter that structurally marginalizes the council's role in the city's strategic political future. The council still puts most of its energy into land-use issues, which mayors still avoid like the plague.

And while we may fashion ourselves a city of increasingly cosmopolitan impulses, our politics remain riven by race and class, and tainted by timidity and provincialism. A succession of mayors have placed high priority on reversing underperformance and racial apartheid in public education, but they have lacked the political will to make investments that achieve much more than incremental change. The simple, decent act of writing basic sexual orientation rights into local law remains a political hot potato, and our politicians still feel compelled to pray in public all the goddamn time.

Former news anchor and radio talk-show host Teddy Bart, a keen observer of Nashville politics for three decades, senses a widening gap between citizens and their public officials that began with Bredesen. "The pols are more untouchable," Bart says. "This represents the Bredesen persona—aloof, distant, cool, bottom-line, efficient. Where we used to be the personification of Frank Skeffington—the old political boss running for re-election as mayor in the film The Last Hurrah—over 20 years we have become more like the computer HAL in the film 2001: A Space Odyssey." City government may be "cleaner, smarter and more efficient," he adds, "but where's the schmaltz?"

Schmaltz deficit notwithstanding, we're fortunate to have an ongoing electoral tradition where progress—at least in modest terms—consistently wins out over reactionary alternatives. Twenty years ago, the state of Tennessee had a Democratic governor and two Democratic U.S. senators. Today, Nashville appears as a blue island in a red sea. Since the early days of Metro we've elected mayors with forward-looking approaches to the city's future and expansive takes on local government's role in getting there. Truly conservative candidates often run, and they always lose. So far.