One could almost envision the forces of evil invading from the North. The governor of Florida, a man who serves orange juice rather than whiskey at affairs of state, was at the podium.

"Gambling casinos are like vacuum cleaners," he declared, his eyes flaring with indignation. "They suck everything up."

They "degrade the quality of life," they attract crime "like blood attracts sharks," they ruin families and they threaten to turn Florida into another Las Vegas, a place of unmitigated sin, he continued.

"Anyway you cut it," he added "it's a bad roll of the dice."

This is Reubin Askew on crusade.

There's nothing phony about it. Askew, a lame'duck governor, is simply a deeply moral man. And he has fire in his belly over Proposition 9, a constitutional amendment that would allow casino gambling on a 21-mile stretch of Florida's Gold Coast.

So, he is spending almost the entire fall stumping the state raising money to defeat the amendment and preaching against the evils of grambling.

"He's truly acting like his life is at an end over this issue," said Sanford publicist who heads "Let's Help Florida," the pro-casino group that collected 420,000 signatures to put the referendum on the ballot.

Askew's involvement has helped make the referendum the most emotional issue to hit this state since Anita Bryant led a campaign against Dade County's gay-rights ordinance in June 1977. It has completely overshadowed the race to pick a successor to Askew, who is retiring after two terms.

Th campaign has all the elements of a holy war, a clear-cut fight between good and evil. Both sides agree as much. What they disagree on is what constitutes good and evil.

Weiner, who headed the drive to open up Atlantic City to gambling in 1976, argues that casinos will bring nothing but good to Florida.

Casinos, his literature claims, will "guarantee" $120 million annually in new tax dollars for schools and police, triple the number of tourists, create 89,000 new jobs and save once-fashionable Miami Beach from becoming the world's largest geriatric ward.

As for casinos attracting crime, Weiner declares: "That's thoroughly a paper tiger . . . The same argument was made in New Jersey. Under the strong laws that are in New Jersey and that the legislature would put in here, there's no way organized crime is going to get a fool in the door. Organized crime makes money where gambling is illegal, not legal."

He is trying to portray his $2 million campaign, financed chiefly by the owners of five big. Miami Beach hotels, as one of the "people against the establishment." A T-shirt with the sologan "Up the Establishment" hangs behind his desk. A statue with the words "Gov. Goody Askew" is nearby.

Whatever else it is, the campaign is certainly different that it was in New Jersey two years ago. For one thing, the anti-casino forces here are almost as well-financed as the pro-casino ones.

And unlike New Jersey, where Gov. Brendan T. Byrne and the Atlantic City Press supported casinos, virtually the entire Florida political, business, media and religious establishment has lined up behind the anti-casino campaing.

Askew's "No Casino for Florida" group has raised $806,552, including $117,500 from newspapers, news executives and broadcast companies. The state's parimutuel industry, fearing casinos would cut into its profits, plans to raise $700,000. And "Floridians Against Casino Takeover," headed by former Miami Beach mayor Jay Dermer, has raised $93,000.

The media donations, including $10,000 from the Miami Herald and $25,000 from the St. Petersburg Times, stirred a storm of protest both inside and outside the industry. When the Miami News contributed $12,500 to the Askew campaign, for example, 47 staff members protested in a letter to the editor.

"Our deep convictions are that any such political donation by the corporate side of a newspaper tends to compromise the positions of members of the working press," the letter said.

Weiner has capitalized on the donations, charging that they have created an anti-casino bias in news reports, especially in the influential Miami Herald.

"There's no doubt the coverage in this race has gone beyond editorial opposition," he said in an interview. "There's no doubt that reporters have gone back to their offices with objective stories or tapes, but the time the story runs in the paper or the tapes are played on the air, someone has done something to them."

When asked to, however, Weiner last week could not produce any specific examples of bias. The National News Council, a press-monitoring group, has investigated his charges and has agreed to rule on them at its next meeting, after the Nov. 7 election.

What concerns many reports is that the donations give the appearance of partiality, whether real or imagined, and that this will undermine their credibility.

John McMullan, executive editor of the Miami Herald, for example, has written that he would have preferred that his paper not make any contribution. "Yet editors on any newspaper," he added, "can't ignore the obvious fact that our business officials have consciences, too, and they also have a stake in the quality of life and economic health of the community."

Currently, the odds are running against casinos in Florida. Polls last month by the Miami Herald and the St. Petersburg Times showed the referendum going down by a wide margin.

Yet many are hedging their bets. More recent polls by both pro and anti-casino forces found the race close.

Both sides have been guilty of rhetorical overkill.

Weiner's projections of the tax dollars and tourist that casinos would attract are highly suspect. They are based on "unsupported assumptions, inconsistencies, erros and misrepresentations," including the unlikely assumption that South Florida would have 15 casinos by 1990, a report by the Florida House Finance and Taxation Committee declared last week.

Yet it is well-known that many of the nation's top organized-crime figures, including Mafia elder statesman Meyer Lansky, maintains homes in Florida. And a 10-year study for the Law Enforcement Assistance Administration suggests that police officers and the FBI created the image of organized crime control of gambling to explain their failures to stope illegal gambling.

On the surface, Askew appears to be gaining ground. After he spoke to the Palm Beach Chamber of Commerce here the other day, he asked those who agreed with him to raise their hands. Three-quarters of the crowd of about 400 did.

"I'm still not convinced," said Ben Johnson, a realtor. "Askew keeps talking about crime around casinos. I go to Monte Carlo every summer. I don't see any rapes and murders going on there."

"My suspicion is a lot of people are keeping quiet because there are a lot of very prestigious people who are against it," a lawyere said. "When they get in the voting booth, I think it's going to be much closer than people think."

Even if he is wrong, anti-casino forces have another fear. They think they can defeat the referendum this year, but the big hotel operators will come back with another one in 1980. When that happened in New Jersey, pro-gambling forces won the second time.