WASHINGTON -- If you’re one of Nevada's 200,000 casino workers, you’re probably going to be getting a memo from your employer about the upcoming Nevada caucuses. The American Gaming Association has distributed a voter information guide to its member companies to hand out to employees.

The guide, a first for the casino trade group, aims to show employees where various presidential hopefuls stand on the issue of casino gambling. It lists candidates from both parties and grades them based on their positions.

Democratic front-runner Hillary Clinton's name appears next to a green dot to indicate that she's “Open/Supportive” to gaming, while Sen. Bernie Sanders (I-Vt.) gets a yellow dot and a "Mixed" review because there is “No information available” about where he stands. Republican candidate Jeb Bush has a red dot next to his name, meaning he's “Opposed” to gaming.

The guide is careful to note that its classification of the candidates is not meant to constitute an endorsement of any of them.

“We completely respect the right and the privacy people have to make their own decision and this is just one piece of information that is part of the many sources of information that they are getting about each of the candidates,” American Gaming Association spokesman Christopher Moyer said.

Yet in the post-Citizens United world, corporations and their trade associations don’t have to be quite that careful. The 2010 Supreme Court ruling that opened the door to unlimited corporate and union campaign spending also allows corporations and unions to communicate directly with employees and members about elections. They can tell them who they should vote for -- and, in most states, compel them to do political work or appear at rallies for the candidates management supports.

HUFFPOST READERS: Has your employer ever encouraged you to vote a certain way? Compelled you to attend a political event or do political work? Distributed political materials in the workplace? Let us know at openreporting@huffingtonpost.com. You can remain anonymous if you prefer.

The American Gaming Association doesn't fully embrace its ability, courtesy of Citizens United, to endorse candidates. The group's voter guide would probably pass muster in the pre-Citizens United days, says Larry Noble, a lawyer for Campaign Legal Center and former general counsel for the Federal Election Commission. But “What Citizens United did was make it very clear that they could publish something like this,” he said.

Since the 1970s, campaign finance laws have restricted how corporations and unions communicate about politics and elections with their employees and members. However, those laws did not envision a post-Citizens United world in which corporations and unions could use their treasury funds to engage their staff or membership. This has left a nearly unregulated landscape in most states for political communication to corporate employees or union members.

Evidence shows that corporate management and union leaders will continue to take advantage of their new freedom to inject politics into the workplace and compel workers or members to back their favored positions or preferred candidates.

During the 2012 campaign, Westgate Resorts CEO David Siegel penned a memo to his employees saying their jobs would be at risk if President Barack Obama was re-elected.

“The economy doesn’t currently pose a threat to your job. What does threaten your job, however, is another four years of the same presidential administration,” Mr. Siegel wrote. “If any new taxes are levied on me, or my company, as our current president plans, I will have no choice but to reduce the size of this company.”

David Becker via Getty Images Westgate Resorts CEO David Siegel told his employees that their jobs could be on the line if Barack Obama was re-elected in 2012.

That threat didn't pan out. Even though Obama won, Siegel increased the minimum wage at his timeshare company in 2015 after the best year in the corporation’s history.

Georgia-Pacific, a paper product company owned by the billionaire Koch brothers, distributed a political endorsement flier to its employees during the 2010 and 2012 elections. As In These Times reported, Koch Industries funded the flier, which contained a cover letter that implicitly threatened job loss based on the outcome of the election:

If we elect candidates who want to spend hundreds of billions in borrowed money on costly new subsidies for a few favored cronies, put unprecedented regulatory burdens on businesses, prevent or delay important new construction projects, and excessively hinder free trade, then many of our more than 50,000 U.S. employees and contractors may suffer the consequences, including higher gasoline prices, runaway inflation, and other ills.

Koch Industries employees received a very similar flier during the 2010 election, according to The Nation.

Chief executives at companies like Rite-Hite, an industrial equipment manufacturer in Milwaukee, and ASG Software Solutions in Naples, Florida, also sent out anti-Obama messages to employees.

Rite-Hite CEO Michael White emailed his 1,400 employees to tell them that if Obama were re-elected, they could lose their insurance. “Every opportunity to make up for lost profits to taxes will have to be evaluated," he threatened.

Mitt Romney, the Republican presidential nominee in 2012, used a call with small business owners to urge them to politicize the workplace by making “it very clear to your employees what you believe is in the best interest of your enterprise and therefore their job and their future in the upcoming elections.” Romney assured them that there was “[n]othing illegal about you talking to your employees about what you believe is best for the business.”

The U.S. Chamber of Commerce, the nation’s largest corporate business lobby, encouraged member companies to include electoral messages in envelopes containing employee pay stubs in 2012.

Perhaps the most notable case of corporate political communication to employees occurred in Ohio, when Murray Energy -- headed by Republican party megadonor Bob Murray -- compelled workers to forgo a day of paid work to appear at a Romney rally that would be turned into a campaign advertisement.

Kevin Hughes, a manager at Murray Energy, told workers their attendance was “mandatory,” although Murray Energy's chief financial officer later stated that “no one was forced to attend the event.” In an FEC investigation into the incident, Hughes said that there was confusion about what he meant by "mandatory":

If I used the word "mandatory" it would have been in the context of conveying that opposing the Obama Administration policies was mandatory if the coal industry is to survive.

That FEC investigation ended in a 3-3 deadlocked vote. Another FEC investigation into alleged coercion by a United Public Workers local in Hawaii -- which allegedly forced members to campaign for former Democratic Rep. Colleen Hanabusa -- ended similarly.

As the Republican commissioners stated in their vote in the United Public Workers case, “UPW’s independent use of its paid workforce to campaign for a federal candidate post-Citizens United was not contemplated by Congress and, consequently, is not prohibited by either the Act or Commission regulations. ... Requiring employees to work on independent expenditures for either the union or a non-connected political committee is not a violation of the Act or Commission regulations.”

With a paralyzed FEC that may not even have the authority to act on corporate political messaging and coercion in the wake of Citizens United -- and a Congress that will not pass any updates to the law -- employees and union members can expect to see even more of these activities in 2016 and beyond.

HUFFPOST READERS: Has your employer ever encouraged you to vote a certain way? Compelled you to attend a political event or do political work? Distributed political materials in the workplace? Let us know at openreporting@huffingtonpost.com. You can remain anonymous if you prefer.

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