Ryan Sitton of the Railroad Commission of Texas said there’s a basic frustration with his job: People keep asking him about railroads.

“People don’t know the job, and they think we are the train guys,” said Mr. Sitton, an elected commissioner on the state’s oldest regulatory agency, created in 1891.

He estimated that only 1 of 10 Texans knows the commission’s main function, and that it has nothing to do with railroads, despite elections every two years to fill one of its three statewide positions.

The Railroad Commission’s main task is to regulate oil and gas operations. It has been one of the most powerful offices in Texas for 100 years, since a mammoth oil boom put the state on the economic map.

Mr. Sitton said it’s time to rebrand.

Other state officials are reluctant, saying the name is a throwback to the original days of the oil boom. Numerous bills put forth in the Texas legislature to change the name to accurately reflect the agency’s duties have failed.

A gusher

“It’s a historical name. It has a lot of meaning across the world,” said Lauren Spreen , director of public affairs for Commissioner Christi Craddick , who is chairman of the commission and doesn’t want the name changed. She said Ms. Craddick, a Republican running for re-election in November, talks to Texans daily about what the agency does.

Her Democratic opponent, Roman McAllen, said the name needs to change because it is too obscure. “It’d be like calling the Food and Drug Administration the National Football League,” Mr. McAllen said. “This is about basic transparency. People come up to me all the time and ask, ‘When are we going to get high-speed rail?’ ”

Even political insiders are confused by the name, Mr. McAllen said. He recalls a Minnesota congressman who showed up at a Democratic fundraiser in August and thanked him for running for the seat, saying: “The railroads are so important.”

Members of the Texas Railroad Commission—which, despite its name, regulates the oil industry—in 1940. Photo: Associated Press

Some Texans believe the name has been kept for nefarious reasons, to lessen public involvement in the agency by keeping voters clueless about its true function. Since November, just one person has addressed the commission during the public-participation part of its regular open meetings, usually held once or twice a month in Austin. Meetings cover matters ranging from drilling disputes to setting monthly allowable oil production rates to assessing penalties for safety violations.

“I think they like it to be obscure,” said Mark Miller , who had unsuccessful runs for the commission in 2014 and 2016 and made changing the name one of his priorities. “They like that people don’t actually know what they’re voting for.”

The railroad across the Great Plains of Vernon, Texas, in 1939. Photo: Lee Russell/Library of Congress

The commission was created in the 19th century to regulate railroads—in part to keep owners from extorting money from farmers and others to ship their goods. Later, the commission was also charged with regulating oil and gas pipelines. Over the years, railroad oversight was shifted to other agencies, with the final involvement in rail transferred to the Texas Department of Transportation in 2005.

That leaves the Railroad Commission’s roughly 750 employees to focus on oil, gas, pipelines and mining—and many Texans with train questions frustrated.

Mr. Sitton was tagged on Twitter recently by someone with concerns about trains blocking traffic. After explaining that his office has nothing to do with railroads, Mr. Sitton got back this response: “If it looks like a duck, swims like a duck, and quacks like a duck, then it probably is a duck. [The Texas Railroad Commission] certainly failed the Duck Test.”

The current chairman of the commission, Christi Craddick, above, doesn’t want to change the name, while Commissioner Ryan Sitton, below, is in favor. Photo: Railroad Commission of Texas

Photo: Railroad Commission of Texas

The Lone Star chapter of the Sierra Club, an environmental organization, fears people with environmental issues, such as land-use concerns with gas wells, might not know where to turn. “People wouldn’t think to call the Railroad Commission,” said Cyrus Reed , conservation director for the club.

Some lawmakers said a name change would require an amendment to the Texas Constitution, with two-thirds of lawmakers in each chamber approving to put the question to voters, which would then need a simple majority to pass.

Longtime state Rep. Tom Craddick , a former speaker of the House and Ms. Craddick’s father, is an outspoken critic of efforts to change the name and has helped defeat bills on the subject.

Mr. Craddick represents an area of Texas that holds the Permian Basin, which pumps a third of all crude oil produced in the U.S. from its location in West Texas and southeast New Mexico, according to the Permian Basin Petroleum Association.

Mr. Craddick said changing the name would mean renegotiating contracts with the federal government that deal with environmental matters, although some supporters of a name change disagree. “It could be very negative…a lot has changed environmentally since the 1930s and ’40s,” said Mr. Craddick, a Republican who sits on the state’s House Energy Resources Committee.

A worker at Endeavor Energy Resources’ Big Dog Drilling Rig 22 in the Permian Basin outside of Midland, Texas. Photo: Brittany Sowacke/Bloomberg News

“It’s booming out here—we’ve got 400 rigs running,” Mr. Craddick said. “I’m looking at how it’s going to A. Affect my district; and B. The United States as a whole.”

As for Texans not being familiar with the commission, Mr. Craddick said, “The vast majority of people that deal with the Railroad Commission know what it is.”

Former Texas state Rep. Larry Phillips , now a state district judge, authored a failed bill in 2015 to change the name to the Texas Energy Commission. The Republican told the story of an elderly constituent upset about a railroad-crossing closure and getting more upset that the commission couldn’t help. “If she’s confused, that’s good enough for me,” he said.

A name change could trigger costs to change signs and logos. Estimates have run from $100,000 to $500,000.

“It’s just not our priority to spend that kind of money on a name change,” said Ms. Spreen, the public affairs director on the commission.

For the third railroad commissioner, Wayne Christian , who was elected for his six-year term in 2016, the possibility of further regulation and costs puts him in the “leave it alone” camp.

Mr. Sitton, tired of explaining the name on a nearly daily basis, said money shouldn’t be the issue. “We work for the people of the state, and they should know what we’re doing,” he said. “I will raise the money.”

Write to Tawnell D. Hobbs at Tawnell.Hobbs@wsj.com