ENCINITAS, Calif.—The campaign to repeal California's gas-tax increase was outspent roughly 10 to one and faced an onslaught of negative ads but the outcome appeared too close to call in the final days of the election.

The gas-tax repeal campaign on Monday held events at gas stations throughout Southern California, offering a chance to win a free tank of gas and waving "Yes on Prop 6" placards.

Most drivers who showed up at an Encinitas gas-station near the 5 freeway over the course of one-hour Monday morning were vocally backing Prop 6 or agreed that state gas taxes are too high and wanted to learn more about the initiative. Only three out of 12 drivers the Washington Free Beacon asked for comment declined to speak.

"All this time, where did the money go for our infrastructure? The gas-tax was for that—well, where are other taxes going? Everything keeps increasing in California, and I just think it's poorly run by our governor," said Michaelaine Peeble, who said she had voted early and marked the ballot in favor of the gas-tax repeal.

The interviews reflect the late-election findings of a new poll conducted by SurveyUSA and paid for by the San Diego Union-Tribune. The survey found that Prop. 6, the official name of the repeal, was too close to call with 44 percent in favor, 41 percent opposed and 14 percent undecided.

The results surprised proponents and detractors alike because a number of other recent polls had found support for Prop 6 trailing badly after a slew of ads warning of dire consequences for the state's roads and bridges if it passed.

"The main difference in the surveys was the wording," the Union-Tribune acknowledged in a Sunday piece. Polls that used the deceptive ballot title Democrats in Sacramento gave it—"Eliminates Recently Enacted Road Repair and Transportation Funding by Repealing Revenues"—found that voters were likely to keep the tax increase, that began in January.

However, the most recent SurveyUSA poll, released late last week, that asked likely voters if they wanted to "repeal gasoline and diesel taxes and vehicle fees" found voters favored Prop 6 by a 2-to-1 margin.

Carl DeMaio, a conservative talk show host who spearheaded the gas-tax repeal campaign, has slammed the state's ballot wording as "sinister," blaming California Attorney General Xavier Becerra and vowing to recall him over the issue if the gas-tax repeal fails on Tuesday.

DeMaio has spent the last few weeks of the campaign crisscrossing the state in a yellow bus emblazoned with "Yes on Prop 6" and "Gas-Tax Repeal" trying to inform voters about the misleading wording on the ballot and in the ads.

DeMaio's group, Reform California, spent an estimated $5.1 million on its campaign supporting Prop 6 while opponents raised and spent roughly $47 million, California open records show.

The initiative would repeal the new 12-cent gas-tax increase and car registration fee increase and require the statewide electorate approve any gas, diesel, or vehicle-related tax or fee increase.

Californians pay the second highest gas taxes in the country with 74 cents on each gallon of gas going to pay for state and federal taxes, according to the American Petroleum Institute.

Southern California gas prices this summer and early fall are their highest in three years after the latest gas tax was implemented in January. Prices have hovered around $3.87 in the Los Angeles area, nearly $1 more than the national average, reports the Auto Club of Southern California.

By 2021, many Californians will be paying close to $2 more per gallon because of taxes, fees, and other government requirements.

On Saturday, during a stop at GOP candidate Young Kim's campaign headquarters in Yorba Linda, DeMaio touted the new poll and said the effort, if successful, would put a stop to Democratic officials' attempts to raise other taxes they're eyeing after successfully raising the gas-tax and car fees.

"The next 100 hours are so important because they will determine who is really in charge of our government," he said. "[The Sacramento politicians] see you as an ATM machine. They want to raise your taxes … they take your money first and then they go on to take your freedoms."

"We already paid for great roads, we paid the fourth highest gas tax in the country prior to this increase, and now it's the highest gas tax in the country," he said.

Gov. Jerry Brown, who helped push the gas-tax increase through the legislature last year, has called DeMaio a "political terrorist." He argues that the additional gas-tax revenue, some $5 billion a year, is critical for fixing roads and boosting public transit.

Republicans backing the gas-tax repeal argue that Brown and other Democrats want the money because they raided the gas-tax funds for other spending, such as pension funds for public employees, debt payments, and Brown's much-touted bullet train linking San Francisco to Los Angeles. The high-speed rail project is billions of dollars over budget with no completion date in sight.

"It's not only the gas-tax repeal, but what this represents," said Susan Black, who participated in a gas-tax repeal rally Saturday. "If this repeal fails, then the California legislature will basically be given a new path on which they can increase taxes on people—it gives them the feeling that they can essentially issue a blank check, and I want to have a say."

"The [gas-tax increase] gives them a blank check for whatever they want—most of it going to the bullet train I imagine, and that just ticks me off," added her husband, Tom Black, a teacher.