Hillsborough County's supervisor of elections has formally verified a grassroots effort has enough signatures to put a tax referendum on the November ballot.

As 10News reported in July, more than 70,000 people signed a petition to hold a vote on increasing road and transportation funding through a once-cent-per-dollar sales tax increase for 30 years -- a hike that would generate $280 million in its first year.

County leaders voted down a similar tax increase in 2016. And, voters shot down another effort in 2010.

But, with another 700,000 people expected to move into the county in the next three decades, a citizen-led group called All For Transportation is trying again. And, the organization has far surpassed the required 49,000 signature threshold to place the issue on the ballot.

“We’ve waited far too long to solve a transportation crisis in Hillsborough County that is getting worse every day,” Tyler Hudson, chair of All for Transportation, wrote in a statement. “The best time to act was 20 years ago; the second best time to act is today.”

Related: Group says it has signatures to get Hillsborough transportation tax increase on ballot

If approved by voters, the tax increase would help pay for improvements to roads, bridges, rush hour congestion and public transportation -- among other things.

“All of these funds will be reviewed by an independent oversight committee and audited annually to make sure the funds are used as outlined in the plan that voters signed and will vote on in November," Hudson said.

Critics question if the fall referendum could derail the school district's separate plan to ask voters next spring for a sales tax increase.

There are also questions over the legality of holding a referendum that wasn't reviewed by state legislative staff. Some interpret state law as to require a study before any tax issue can be put before voters.

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