COLUMBUS -- Cleveland Cavaliers owner Dan Gilbert said he would start first thing Wednesday making plans for the four casinos that Ohio voters wrote into the state Constitution.

"Let's start lighting it up like Las Vegas," a giddy Gilbert said Tuesday after learning of Tuesday's election results. Gilbert is a main investor in the casino plan.

Passage of Issue 3 marked a significant victory for Gilbert and Penn National Gaming Inc., who spent nearly $35 million to persuade one of America's most stubborn anti-gambling states to change its mind. It marked the fifth time in 20 years a gambling expansion was proposed in the state, with all four previous attempts rejected.

With 99 percent of precincts reporting unofficial results, Issue 3 passed 53 percent to 47 percent.

The issue amends the state Constitution by authorizing casinos in Columbus, Cleveland, Cincinnati and Toledo, sets a 33 percent tax rate and outlines how the money will be distributed. Penn National president David Wilmott predicted all four casinos would be built in a little over two years.

David Zanotti of the Ohio Policy Roundtable, an anti-gambling activist, said citizens of a state with more than 10 percent unemployment were enticed by omnipresent ads promising 34,000 jobs.

"It's pretty obvious that the Ohio electorate bought into the whole culture of despair that's going on with the economy," he said.

Ohio becomes the 39th state to legalize casinos and a coveted prize that had held out among neighboring casino states Indiana, Michigan, Pennsylvania and West Virginia. TruthPAC, backed by MTR Gaming Inc. chairman Jeffrey Jacobs, spent almost $6 million opposing the measure.

Tuesday's vote may not be the end of the story, however.

State Rep. Lou Blessing, a Republican who fought the plan, said he plans to push a ballot issue next May that amends elements of the plan, collects more taxes from the casinos, and put the licenses up for bid.

Lawmakers cannot make changes to the casino outline without going to the ballot because it was inserted into the state Constitution.

"I don't know how even the newspaper that endorsed this issue could possibly object to that," Blessing said. "There are some obvious problems that need to be fixed."

The Humane Society of the United States also vowed a future Ohio ballot issue after it was struck a blow by the passage of Issue 2, which creates a new board to oversee livestock care. The issue was approved by 64 percent of voters, with 99 percent of precincts reporting.

The issue was intended to thwart efforts by animal right groups to outlaw holding sows, hens and veal calves in cramped cages or crates.

Michael Markarian, the Humane Society's chief operating officer, said the group will return to Ohio with a future ballot measure that protects animals.

"By packaging Issue 2 as a pro-animal and pro-food safety measure, the factory farming interests really did everything they could to ensure its passage," he said. "We never really viewed it as a poisonous measure but we viewed it as an empty one, because it doesn't achieve any reforms for animal welfare."

Large farm operators mounted a $4 million campaign to pass the issue, which was backed by Gov. Ted Strickland, while environmental, animal rights and other activists fought it mostly through the press and the Internet.

Ohio voters also passed Issue 1, which will pay bonuses of up to $1,000 to war veterans who served in the Persian Gulf, Afghanistan and Iraq. It was approved by 72 percent of voters, with 99 percent of precincts reporting.

In big-city mayor's races, incumbent Democrats Mark Mallory of Cincinnati and Frank Jackson of Cleveland won re-election.

Voting went smoothly statewide except for a glitch in Summit County, which includes Akron. The county ran out of ballots around 5 p.m. and had to turn away some voters.

Poll workers contacted them and asked them to return after printing more ballots.

The casino fight attracted more than $40.6 million in spending this year -- more than the $40.1 million presidential rivals Barack Obama and John McCain spent trying to win the pivotal swing state in 2008.

TruthPAC spokeswoman Sandy Theis called it a sad day for the state.

"Many Issue 3 supporters genuinely believe it will help Ohio's economic recovery. I hope they are right. I fear they are wrong," she said. "Issue 3 is riddled with loopholes that will shortchange Ohio, muzzle the casino watchdogs and exempt cash wagers from the taxes casinos pay."