Voters searching for a polling place in Contra Costa County came up short for more than five hours Tuesday when the county’s elections website crashed, along with more than a dozen other election sites across the country.

Shasta and Ventura counties in California were experiencing problems, as were Dallas and Denton counties in Texas, Arapahoe County near Denver, and the Georgia secretary of state’s office website, all possibly linked to one Florida elections software company. Most appeared to be operational by about 1:30 p.m. Pacific time.

A total of 18 government election sites nationwide crashed on Election Day, said Maureen Szlemp, North America marketing manager of SOE Software, an elections software company based in Tampa. The only California websites affected were in Contra Costa, Shasta and Ventura counties. Each of the 18 jurisdictions used SOE’s Connect portal website and were not able to handle higher-than-expected traffic Tuesday morning, she said.

“Things are looking much better,” she said. “We’re in the process of redistributing the load among additional servers that will resolve the issue.”

The Contra Costa site (www.cocovote.us) went down about 7:30 a.m., said Contra Costa Assistant Registrar Scott Konopasek, and calls to his office spiked. For more than five hours, voters received error messages and blank screens, and elections officials scrambled to publicize alternative websites to gather polling information.

“It’s one of those things that’s totally out of our control,” Konopasek said.

He did not believe turnout would be affected by the glitch.

“I don’t think you’ll find anyone adversely impacted,” Konopasek said. “It’s not like information was not available; it was just one channel not available for five hours.”

Contra Costa officials have used SOE Software to operate half of the clerk-recorder home page for about seven years, the assistant registrar said, spending about $25,000 to $30,000 each year for licensing, hosting and maintenance costs.

“We will be completely looking at different options for service providers,” Konopasek said, adding their contract ends in August 2015.

Contra Costa registrar officials said election results would be updated with PDF documents posted to the county’s general website after polls closed at 8 p.m. just in case.

The SOE website was down as well Tuesday, before becoming active again. According to its LinkedIn page, SOE “is a nationally recognized leader of election software solutions.”

The company’s products are designed to assist election offices with “web communication, outreach and education, and office productivity,” according to its profile. The company boasts it provides “time-tested” solutions to more than 1,500 jurisdictions in city, county and state government offices in 34 states across the country.

The Georgia secretary of state website had intermittent problems with the page that informs voters of their polling locations, as did Johnson County, Kansas.

Voters on social media sent angry messages to the affected agencies, expressing shock the sites would go down on such an important day.

From his Twitter account, Georgia state Rep. Scott Holcomb wrote: “amazing — just logged onto Georgia Secretary of State website and it is down. On Election Day. #FAIL.”

Other government agencies also use SOE Software and reported no problems, including Santa Clara, Sacramento, Los Angeles and San Diego counties and states from Alaska to New York. Even Broward County, Florida, three hours away from SOE headquarters, said they operate with the company’s software and had no problems Tuesday.

The Denver Post and The Associated Press contributed to this report. Contact Matthias Gafni at 925-952-5026. Follow him at Twitter.com/mgafni.