Although the school choice movement is becoming more bipartisan, it's clear the largest obstacles to school choice at the legislative level come from Democrats. That said, nominating Donald Trump for president could have disastrous effects for school choice.

The main reason is that Trump would be unable beat Hillary Clinton. Since May 2015, there have been 58 different polls that asked voters to pick between Clinton and Trump. Although Trump led five of those polls, he has led in none since early February. An average of polls since mid-March gives Clinton more than a 10 point advantage over Trump, and his unfavorable rating is near or at 70 percent in three recent polls. He also underperforms Ted Cruz and John Kasich.

Trump's negative coattails would be helpful not only for Clinton, but for other Democrats on the ballot as well. This includes state-level elections, where 12 gubernatorial matchups and 86 of the nation's 99 state legislative chambers are holding elections in 2016.

As Chester Finn points out in Education Next, this would be bad news for conservative reforms at the state level, particularly education. The progress of school choice could be stopped in its tracks and even undone in certain states. "The good news for reformers, if there is any, is that the kinds of changes that bring actual, tangible benefit to thousands of families are hard to undo (though their growth may be curbed and their operations slowly impeded)," Finn writes.

Washington State provides a good example of this dynamic in action. In March, a bill to allow public charter schools operate in the state narrowly passed the state senate on a 26-23 vote, with three Democrats in support. The governor, a Democrat, decided to allow the bill to become law without signing it. But if not for a few key victories by Republicans in the last election, this would not have been possible.

Pretend for a moment that the bill were to come up a year later, after Clinton beats Trump in Washington by 30 points and Democrats take a large majority in the state House and Senate. It's extremely unlikely that bill ever makes it through the Senate.

In Nevada, the state passed one of the most important educational choice programs in the country in June 2015. More than 95 percent of students in the state are eligible for an education savings account that lets them use most of their state education funding for almost any educational need.

That program passed without a single vote of Democratic support in the legislature. It never would have happened if Democrats had more control. It seems unlikely the program could be repealed after 2016 since Gov. Brian Sandoval, a Republican, will be in office through 2018. But other states across the country would be kept from making such significant gains for educational choice if Democrats win landslide victories on the state level in November.

A Clinton win would also be very helpful for teachers' unions that are working to stymie reform efforts. Any Clinton Supreme Court nominee could be counted on to side with the unions were another case like Friedrichs v. California Teachers Association to come up, posing a potential threat to union privileges. The particular issue in that case, which has to do with unions using unwilling members' money to fight school choice, could be pivotal in making further progress.

Much ink has been spilt on the down-ballot effects of a Trump nomination: the Senate goes to Democrats, perhaps the House as well, and a liberal justice is certain to replace the late Antonin Scalia. But it's also important to remember the state-level effects of a Trump nomination, and the effects of those losses will have on public policy. If the spread of school choice stalls, students will be left stuck in failing schools.

Jason Russell is a commentary writer for the Washington Examiner.