Epic battles for power and control in Sonoma County's two largest cities and on the board of supervisors will conclude Tuesday, and depending on the outcome, could change the political landscape for years to come.

"Change" was the buzzword in 2008 when Barack Obama was swept into office and locally, when candidates backed by environmentalists helped wrest control of the city councils in Santa Rosa and Petaluma.

Candidates backed by business interests are now hoping to regain power in those cities, and also deflect a political tilt on the board of supervisors, where a business-friendly majority still reigns.

"There's a tremendous amount at stake in that you have two philosophies going head-to-head for who will dominate the politics of Sonoma County," said Brian Sobel, a former Petaluma city councilman and now a political consultant.

"You've got a moderate-to-pro-business faction, and you've got a moderate-to-progressive faction," he said. "That means there are a whole lot of people in the middle who, under the circumstances, might lean one way or the other."

Gobs of money are being poured into the respective races, including a pace in the 2nd District supervisor's race that could eclipse the 2008 record of $700,000 set by 3rd District candidates Sharon Wright and Shirlee Zane.

Pam Torliatt, viewed as the slow-growth, pro-labor candidate, is running against David Rabbitt, who has earned support from the Sonoma County Farm Bureau, building and trade groups, and local police and firefighter unions.

Petaluma environmental activist and former county supervisor Bill Kortum, a Torliatt supporter, called the election a "watershed for how the future's going to go."

Kortum said the county's environmental future is at stake, and as evidence of that, he pointed to the board's recent approvals of the Dutra asphalt plant on the Petaluma River near Shollenberger Park and the Roblar Road quarry west of Petaluma, both on 3-2 votes.

"Despite these protections that voters voted in, and use their pocketbooks to protect, a couple of lame-duck supervisors pushed through these insulting and unneeded projects," he said.

He said the board's upcoming decision on Preservation Ranch, which would place about 1,800 acres of vineyards on 20,000 acres of heavily logged land in the northwest section of the county, outside Annapolis, is another example of why the election matters.

But Eric Koenigshofer, a former county supervisor and spokesman for Premier Pacific Vineyards of Napa, the developer of the timber conversion project, said there is no risk to the county's strong environmental protections after Tuesday.

"What this change could bring is not a threat in any real way to those values, but what pro-business means in terms of our environmental construct," he said. "It's a process that is not only sensitive to our environmental values, but has some practical applications of project review and how long it takes."

The outcomes of Tuesday's races are likely to depend in large part on who voters believe have the best plans to address problems with the poor economy, the acknowledged key issue in this year's election cycle.

Generally speaking, the candidates backed by business interests talk about the need to attract and start new businesses, including streamlining and speeding up the permit process.

The candidates backed by slow-growth advocates say the infrastructure is there and discuss filling vacancies and attracting "green jobs."

In Santa Rosa, a slate of three business-backed candidates is hoping to wrest back control of the City Council, which underwent dramatic change in 2008.

That year, candidates who were focused on environmental and quality-of-life issues took over after decades of control by largely pro-development City Council majorities.

The new majority includes Mayor Susan Gorin and Councilmembers Veronica Jacobi, Gary Wysocky and Marsha Vas Dupre, and they have wielded their influence, including shooting down a proposal for a Lowe's home improvement store in south Santa Rosa.

Gorin and Jacobi are seeking re-election. A third seat is up for grabs with the retirement of Councilmember Jane Bender.

The business-backed candidates vying for those seats, Scott Bartley, Jake Ours and Juan Hernandez, accuse the incumbents of setting the city on course for financial disaster.

They've received backing from Santa Rosa's police and fire unions, which have joined forces with the county's largest builder and business groups to build a $40,000 war chest that is being used to try and unseat Gorin and Jacobi.

Bender, who was attacked as a pro-business candidate when she was first elected to the council in 2000, lamented that the candidates have been divided into two camps. She said the reality is more nuanced.

"The public thinks, if someone is pro-business, they must be anti-environment. I really wish we didn't have to think in dichotomies," she said.

That split is also playing out in Petaluma, where four candidates are vying for the mayor's post and nine for the three City Council seats on the ballot.

Members of the current 4-3 majority on the council stress transit-oriented development and strict environmental oversight of proposed developments, all principal tenets of "smart growth."

The minority contends that the city's general plan and zoning codes provide most necessary planning oversight.

Sobel said those divisions may fade once new councilmembers and a supervisor take office, and the reality of the economic crisis sinks in.

"The silver lining is that over the next 18 months to two years, all these bodies are going to be forced to get along because there aren't other ways to fix the problem," he said. "If they don't get along, they won't be there. The public is as on top of what's going on now as I've ever seen them."