A fourth group emerged today opposing the proposed sales tax hike in the May 5 election, this one led by a political consultant who twice helped the proposal's biggest backer — Gov. Rick Snyder — get elected.

John Yob is the lead strategist behind "Citizens Against Middle Class Tax Increases," which plans a grassroots campaign against the proposed hike in the state sales tax to 7% from 6%.

"This is a 17% tax increase directly on the middle class," Yob said in a news release. "It is wrong to ask hardworking, struggling, middle class families to foot the bill."

Yob is CEO of Strategic National Consulting LLC of Grand Rapids, which advised Snyder's gubernatorial campaigns in 2010 and 2014.

The proposed sales tax hike is now the centerpiece of Snyder's plan to raise an extra $1.2-billion to fix and maintain the state's roads and bridges, which the governor says is a critical public safety and economic development issue that is also hitting consumers in their pocketbooks through additional car repairs.