The Senate is set to vote early next week on the confirmation of Betsy DeVos, the Michigan billionaire chosen by President Trump to be education secretary. On Friday, the vote stood at 50 to 50, reflecting the unprecedented opposition that has spread across the country against her. If no senator switches sides, Vice President Pence will have to break the tie to confirm her.

Supporters of DeVos would have everyone think that the opposition to her — the most extensive for an education secretary nominee ever and the most of any of Trump’s Cabinet secretaries — is the work of the teachers unions. The big, bad unions, the story goes, don’t want her because she is on the side of kids and not adult union members, and they will do anything to defeat her.

For example:

It’s certainly true, as my Post colleague Emma Brown

, that the two big teachers unions, the National Education Association (which is the largest labor union in the country) and the American Federation of Teachers — traditionally Democratic allies — did gear up to oppose her the second after she was nominated. But the opposition against her is bigger than that — and looking at it through the traditional political lens doesn’t quite capture the broad nature of it and what is propelling it. School choice has been pushed by Democrats and Republicans alike, including by the Obama administration, which in its pursuit of corporate-style education reform infuriated the teachers unions. Public school advocates for years have accused Democratic reformers of acting like Republicans.

Yet school choice backers who have been hostile to the teachers unions have come out against DeVos because they don’t see her in the mainstream of their education thought. Her defenders, such as Senate Education Committee Chairman Lamar Alexander (R-Tenn.), have insisted that she is not an education extremist. But her critics say that anyone who would call the public school system a “dead end” — as DeVos did in 2015 — does not have sufficient interest in improving it but would rather seek to privatize it — and that is a line they don’t want to cross.

Take billionaire Eli Broad, who has poured hundreds of millions of dollars into charter schools and other corporate-based reforms. Broad just sent a letter to Senate leaders urging them to vote against DeVos, saying, “At the risk of stating the obvious, we must have a secretary of education who believes in public education and the need to keep public schools public.”

Broad is a big Democratic donor and was a Hillary Clinton supporter, but unions hardly see him as a friend. This 2015 story in the LA School Report noted: “With his massive plan to enroll half of all LA Unified’s students into charter schools, billionaire philanthropist Eli Broad is threatening major disruptions at LA Unified, cementing his role as Public Enemy No. 1 to many district and local union leaders.” And he donated $1 million to the 2014 campaign of an anti-union leader to be superintendent of public instruction in California.

The group Democrats for Education Reform, which supports school choice and has been highly critical of teachers unions, said it couldn’t support DeVos in a statement from its president, Shavar Jeffries. Jeffries wrote: “In particular, Mrs. DeVos’s testimony [during her Jan. 17 confirmation hearing before the Senate Education Committee] was noncommittal on whether public schools should be defunded or privatized.” Also opposing her is Whitney Tilson, a wealthy hedge fund manager who helped found DFER and Teach for America, a group that has angered unions. He wrote in 2015 of how DFER “achieved particular success in breaking the stranglehold the teachers unions used to have on the Democratic Party.”

Yet DeVos is too extreme a school choice supporter for DFER and Tilson.

Parents across the country who have children with disabilities, as well as the groups that represent them, have urged senators to reject her — not because the unions asked them to but because they were shocked when DeVos appeared not to know at her Jan. 17 confirmation hearing that the Individuals With Disabilities Education Act is a federal law that states must implement.

For example, the American Association for People With Disabilities said in a statement:

The mission of the department of education must be to advance a national system of quality public education and protect the rights of all children, including children with disabilities, within that system. Ms. DeVos’s testimony during her confirmation hearing, together with her lengthy record of supporting the diversion of public tax dollars to private schools that limit the rights of students with disabilities, indicate that as secretary she would undermine that critical mission.

My Post colleague Emma Brown wrote in this story about a Tennessee mother of a son with disabilities, who is suing her traditional school district because she think it did a lousy job educating her son. She is homeschooling her child because she can’t afford a private school. She might be the perfect person to side with a school choice proponent like DeVos, but she doesn’t support the nomination.

Whatever you think of the NEA and the AFT, the “it’s the unions” mantra of DeVos supporters suggests that they can’t fathom that any American not carrying the teachers unions’ water could have personal, legitimate reasons to oppose her.

It is reminiscent of former education secretary Arne Duncan, when in 2013 he chided opponents of the Common Core State Standards as “white suburban moms who — all of a sudden — their child isn’t as brilliant as they thought they were, and their school isn’t quite as good as they thought they were.” Duncan couldn’t quite believe that people could have had a legitimate reason beyond self-interest for opposing the Core.

And it brings to mind the constant refrain of corporate school reformers who keep saying that opponents of high-stakes standardized testing and school choice simply want to maintain the “status quo” and only care about teachers’ jobs.

In an effort not organized by teachers unions, hundreds of alumni and students from her Christian alma mater, Calvin College, wrote a letter saying she didn’t care enough about traditional public education and wasn’t qualified.

Sen. Lisa Murkowski of Alaska and Sen. Susan Collins of Maine are two Republicans on the Senate Education Committee who have come out against DeVos — and they don’t do the bidding of the teachers unions. Senators have said that they are being deluged with phone calls, visits and messages urging them not to confirm DeVos — and certainly a good deal of that has been encouraged by the unions and progressive groups.

Sandra Stotsky, professor emerita in the Department of Education Reform at the University of Arkansas, and a strong critic of the Common Core State Standards who developed one of the country’s strongest sets of academic standards for K-12 students while serving as senior associate commissioner in the Massachusetts Department of Education from 1999-2003, is no fan of the teachers unions. Yet she doesn’t want DeVos confirmed either, believing DeVos is a supporter of the Core even though DeVos says she isn’t.

Even Teen Vogue ran some articles questioning the DeVos nomination, including one with this headline: “10 Public High School Teachers Explain Why They’re Worried About Trump’s Pick for Education Secretary.”

The magazine has been publishing articles on issues that would generally be seen to be liberal, such as a personal essay by Hillary Clinton, but its basic mission is to engage young women in issues that interest them.

Workers in a restaurant Sen. Al Franken (D-Minn.) recently visited were against DeVos, he said during the confirmation vote in the Senate Health, Education, Labor and Pensions Committee, which DeVos won on party lines. The full Senate will vote on her nomination early next week. Franken said:

I have not gotten as much response to any nominee as I got to this one. I went to dinner on Friday night with [former] vice president [Walter] Mondale at his favorite restaurant. He took me in the kitchen. … One of the guys in the kitchen said, “Vote against DeVos.” He wasn’t a teacher.

Besides, while there is certainly reason to legitimately criticize the teachers unions, the demonization of them ignores the valuable role that labor has played in helping to create a middle class in the United States — and still could.

If the unions did have as much power as their opponents suggest, the Obama administration would not have pursued education reforms that the AFT and the NEA opposed. In fact members of both unions were so annoyed at the Democratic administration that they passed resolutions against Duncan in 2014.

And if they did have so much power, Hillary Clinton would be president and DeVos wouldn’t be the nominee to head the U.S. Education Department.