Missouri voters have a long history of rejecting general tax increases. But supporters of a proposal to gradually raise the gas tax by 10 cents a gallon believe this could be the year that people say "yes."
With just days to go before Tuesday's election, there is no organized opposition to Proposition D, and not a penny raised to counteract the nearly $5 million raised by supporters.
Missouri Gov. Mike Parson and Lt. Gov. Mike Kehoe both have been traveling the state promoting the gas tax.
At least 30 other states have raised transportation taxes or fees over the past six years.
Missouri's gas tax has not changed since 1996.
In 2014, Missouri voters rejected a proposed sales tax for roads. They also defeated a transportation tax plan in 2002.