Sonoma residents are voting today on a controversial ballot measure that would limit hotel development in the city.

Polls will remain open until 8 p.m.

The outcome of Measure B is likely to turn on votes cast by mail, including those turned in today at one of the polling booths.

As of Monday, the county's registrar of voters reported that 2,829 ballots had been received out of the 4,738 issued, for a return rate of 60 percent. The city has 6,457 registered voters.

Few issues have galvanized the city of 10,000 like Measure B. Its passage could make it exceedingly difficult, if not impossible, to build a hotel or expand an existing one in Sonoma beyond 25 rooms.

Proponents say the initiative will help preserve the city's quality of life, while opponents argue it would chill economic growth.

Roughly $150,000 has been spent on the measure, likely making it the most expensive ballot issue campaign in the city's history.

The Hotel Limitation Measure would cap new hotels or expansion of existing ones to 25 rooms unless Sonoma achieves an annual occupancy rate of 80 percent, which the city has never done. In 2012, the rate was just under 65 percent.

The city's Planning Commission would have to determine that a large qualifying hotel project, defined in the initiative as more than 25 rooms, does not "adversely affect the historic, small-town character of Sonoma" prior to issuing a use permit, which is the city's current policy. That approval could be appealed to the City Council, but under the new ordinance, a four-fifths' vote would be required for the project to go forward.

Protect Sonoma has raised $80,191 and spent $89,191 to defeat the measure. That includes $37,556 in nonmonetary contributions.

City records show Protect Sonoma took in an additional $6,500 in last-minute contributions from three wineries. They included DeLoach Vineyards ($3,000); a.k.a Wines LLC ($2,500) and Ledson Winery ($1,000).

Preserving Sonoma, which is backing the measure, has total contributions for the year of $48,446. That includes $25,000 loaned to the campaign by Larry Barnett, a former bed and breakfast owner and onetime mayor of the city.

As of Nov. 9, the group had spent $57,874, mostly on legal fees related to drafting the proposed ordinance.

You can reach Staff Writer Derek Moore at 521-5336 or On Twitter @deadlinederek.