Republicans are now scrambling to save a House seat in West Virginia.

One of the most pro-Trump House districts in the country, in the most pro-Trump state in the country, is now officially within Democrats’ grasp for November.

On Tuesday, longtime campaign forecaster Larry Sabato moved West Virginia’s 3rd District race between Democrat Richard Ojeda and Republican Carol Miller from “leans Republican” to “toss up.”

The ground in West Virginia is shifting so quickly in Democrats’ favor that this marks the second upgrade Sabato’s Crystal Ball has made to the race in four weeks. So, in just one month’s time, the contest has gone from “likely Republican” to “lean Republican” to “toss up.”

It’s the latest data point supporting the idea of a mounting Democratic blue wave during the midterm election cycle.

The West Virginia seat was vacated when incumbent Republican Rep. Evan Jenkins ran unsuccessfully for his party’s Senate nomination to take on Democratic incumbent Joe Manchin.

Now Democrats in the district are pinning their hopes on Ojeda, a fierce teacher advocate who’s emerging as a possible new star in West Virginia politics.

“Democrats have a uniquely appealing candidate in Ojeda, a retired Army paratrooper who saw combat in Iraq and Afghanistan and became a folk hero during this year’s teacher strike,” noted the non-partisan Cook Political Report.

West Virginia teachers helped ignite a national movement this year when they went on strike for nine days, protesting the severe lack of education funding. Teachers in other red states, including Oklahoma and Arizona, followed their lead, sparking a national conversation about teacher pay.

And Ojeda was a major supporter of that movement.

“It was his outspoken defense of West Virginia’s teachers that pushed him to the national spotlight,” Vox reported. “During the nine-day strike, teachers sported T-shirts and carried posters with Ojeda’s photo and took selfies with him.”

How astounding is it that West Virginia’s 3rd District, located in the heart of coal country, could now go Democratic? In 2016, Trump won that district 50 points, while winning the state of West Virginia by 42 points.

Democrats need to pick up 23 seats in November to gain control of the House. Since World War II, the party out of power has won, on average, 26 seats during a new president’s first midterm election cycle.

On Tuesday, Sabato, after some hesitation, officially dubbed Democrats as favorites to win control of the House.

He pointed to the “extraordinary” fundraising success Democrats are enjoying this year, along with Trump’s historically low approval ratings, as reasons for the prediction.

If red seats like the West Virginia’s 3rd District are now considered toss-ups, that means Republican chances of maintaining control of the House are getting worse and worse.