Associated Press

CLEVELAND — Organizers who want to bring casino gambling to Ohio are citing fears of mass layoffs as arguments for why voters should support their effort to amend the state constitution to allow a casino near Dayton.

DHL Express USA’s planned switch of air cargo carriers could mean as many as 9,000 jobs in southwest Ohio’s Clinton County. Nearby, the closing of GM’s Moraine plant, announced on June 3, could mean another 2,000 out-of-work residents.

Supporters of a $600 million casino and resort near Wilmington say that if voters statewide approve legalized casino gambling, they will create much-needed jobs in the hard-hit area.

‘‘We have something to ease the pain: 5,000 jobs averaging $38,000 a year, including a 401(k), medical and dental benefits,’’ said Rick Lertzman of MyOhioNow.com, a minority partner in the proposed project.

Organizers want to collect enough signatures to allow a vote this November on a change in the state Constitution that would allow one casino. The proposed change would give all 88 counties a share of the casino money, promoted as $211 million a year.

Already, ABX employees are looking to work at the yet-unapproved casino if DHL goes forward with its plan.

‘‘If ABX goes, there won’t be anything left out here,’’ said 32-year-old Brian Meadows, of Reesville. For more than two years, he has loaded and unloaded packages from cargo planes for $10.80 an hour.

‘‘Everyone here is scared for their jobs, and most people are talking about going to the casino. No question,’’ Meadows said.

David Stewart, a Clinton County commissioner, announced his support for the casino after DHL announced it would change air carriers. The decision is expected to cut about 6,000 jobs at ABX Air and as many as 3,000 more from related businesses in Clinton County, according to the Ohio Department of Development.

‘‘The mood down here is grim,’’ Stewart said. ‘‘People are worrying about how they will feed their families and pay the mortgage.’’

If ABX closes as expected, employees will compete with about 2,000 General Motors employees who are slated to lose their jobs at the Moraine plant when it closes some time before the summer of 2010.

Critics, though, have pledged to work against the casino project, which would create 3,000 short-term jobs for construction.

Kelly McInerney, the pastor of the Bible Baptist Church in Wilmington, opposes the casino. He said he understands the area needs jobs — just not casino jobs.

‘‘Casinos are not good for local communities when times are good,’’ he said. ‘‘When times are bad, they only add to the misery. We don’t need a predatory industry in our community.’’

Supporters, though, say as many as 1,500 other jobs would come to the area to serve tourists who would visit the area between Columbus and Dayton. They’ve been running television ads, emphasizing that Ohio is surrounded by states that have casinos or are considering legislation authorizing them.

Casinos are considered mainstream entertainment just about everywhere else, Lertzman said.

‘‘If we were building a $600 million bricks-and-mortar business that would employ 5,000 people and pay $38,000 average, Ohio would roll out the red carpet,’’ he said. ‘‘Instead, because it’s a casino, they roll up the carpet.’’