Lawmakers are poised to wrap up this year’s 40-day legislative session on Thursday debating one of their most politically divisive measures: House Bill 87.

Both supporters and opponents of the legislation predicted Wednesday the proposed Arizona-style crackdown on illegal immigration will pass in some form, but the question is how tough it will be.

House and Senate lawmakers were negotiating the details Wednesday. There are several sticking points, including whether to require many private businesses in Georgia to use a federal program called E-Verify to confirm their new hires are eligible to work in the United States.

The Senate stripped that requirement out of the bill Monday. The House put it back in Tuesday and sent the bill back to the Senate, where the legislation is now awaiting its fate.

"I would be surprised if it doesn't pass," said Republican Sen. Don Balfour, R-Snellville, who voted for a version of the bill passed by the Senate on Monday.

Sen. Curt Thompson, D-Tucker, who has vigorously fought the measure, also predicted some form of legislation will pass despite opposition from him and others in the Senate: “Betting money is that something passes because there is so much pressure.”

That pressure on lawmakers has come from both sides. While supporters of HB 87 say the state needs to act because the federal government has failed to secure the nation’s borders, business sectors, including Georgia’s farming, landscaping and restaurant industries, have been fighting the legislation. Some opponents have threatened to challenge the measure in court or help organize economic boycotts aimed at Georgia if the measure is enacted.

At the same time, divisions have opened up among Republicans and Democrats in the Senate over the legislation. Some Republicans want to pass a stringent crackdown on illegal immigration. But other more rural Republicans are worried the legislation could harm the state’s $68.8 billion agricultural industry, which relies heavily on migrant labor.

Meanwhile, Gov. Nathan Deal, who campaigned last year on curbing illegal immigration, is refraining from offering any advice to lawmakers struggling with the issue. Speaking to reporters at the Capitol on Wednesday, the Republican governor confirmed his staff has been “in consultation” with lawmakers, but he called the issue “primarily a legislative responsibility.” He has not yet taken a position on HB 87.

"The difficulty they have encountered reflects the complexity of the issue," Deal said of the lawmakers, "and certainly it's a very multifaceted issue and a difficult one to come to logical conclusions that will be meaningful."

Like the legislation passed in Arizona last year, Georgia’s HB 87 would authorize police to check the immigration status of certain suspects. It also would punish people caught transporting or harboring illegal immigrants or using fake identification to get a job here.

Proponents of HB 87 complain illegal immigrants are burdening the state’s public schools, jails and hospitals. Opponents say the legislation is unconstitutional and would promote racial profiling, invite costly court challenges and damage the state’s economy.

The Senate is expected to take up HB 87 Thursday. A few options are on the table. Senators could approve the bill as is and send it to Deal for his signature. Or they could object to it and call for a conference committee that would hash out the differences between the two chambers. Or they could amend it and send it back to the House.

Staff writer Aaron Gould Sheinin contributed to this article.