Missouri voters can expect to see a good number of messages in the coming weeks encouraging them to support a higher gas tax to better maintain roads and bridges.

“This is mission-critical for Missouri to succeed,” Dan Mehan, president and CEO of the Missouri Chamber of Commerce and Industry, said Thursday in Independence at a gathering of dozens of mayors, state legislators and transportation officials.

The idea was for mayors to get out and start spreading the word. Voters will have their say on Proposition D on Nov. 6.

Here is the advocates’ case: The Missouri Department of Transportation has for years struggled just to maintain the 33,000 miles of roads and 10,000 bridges it has. It spends $850 million a year on that but falls $825 million short of what’s needed. The state’s gas tax, 17 cents a gallon, is one of the lowest in the country and has been unchanged since the 1990s – and has less than half of the buying power it did in the ’90s.

“And inflation eats away at that every day, and it gets worse over time,” said Ed Hassinger, MoDOT’s chief engineer.

Here’s the plan: Phase in a 10-cent increase over four years, adding two and a half cents a year. That’s for regular and diesel. At 10 cents, the tax raises $310.84 million a year. The state gets 70 percent of that – $217.6 million – and cities and counties each get 15 percent, $46.62 million.

And here’s the modest promise: It’s one piece of a longer-term solution for transportation. It does not, for example, begin to address rebuilding Interstate 70 across the whole state, which MoDOT for years has said is overdue.

“And really what’s in the plan (for the increase) is taking care of the system, and that’s about it,” Hassinger said.

Mehan flatly rejected the idea that MoDOT just needs to cut elsewhere to scrape together the extra money it needs.

“Not true – we’ve done that,” he said. “They’re doing a great job with meager resources.”

Gov. Mike Parson and Lt. Gov. Mike Kehoe both support the ballot issue.

“I think that’s a big piece …” said state Rep. Kevin Corlew, R-Kansas City, who was on a state task force that spent much of 2017 studying road-and-bridge needs and funding. Powerful groups such as the Missouri Farm Bureau and the Missouri Chamber of Commerce also have signed on.

Officials were upfront about the need to craft the right message. In polling earlier this year, a 10-cent increase was rejected by 56 percent of likely voters. But $5 a month for better roads – the same math, just stated differently – polled at 56 percent favorable.

Also, advocates will stress public safety, specifically some of the money going to the Missouri State Highway Patrol. Cities and counties also can direct some of their share to police.

Voters also will likely ask what their own communities will get. Officials might develop a list of specific projects. The 15 percent share for cities and counties is a selling point. Locally, that would mean $1.84 million annually for Independence, $826,000 for Blue Springs, $202,000 for Grain Valley, $1.44 million for Lee’s Summit and $52,000 for Sugar Creek. On top of that, Jackson County would get $551,000.