WASHINGTON – On his way to work Friday, David Malone, a special education English teacher at Widener Memorial School in Philadelphia, did what he and thousands of others have been doing for several weeks.

He tried to call Republican Sen. Pat Toomey to oppose President Donald Trump’s nomination of charter school advocate Betsy DeVos to be education secretary.

Unable to get through to Toomey’s office, Malone called again during his lunch break, in his empty classroom, and still had no luck.

“I’ve gotten nothing but busy signals,” he said.

Toomey has been on the hot seat since two other Republican senators — Maine’s Susan Collins and Alaska’s Lisa Murkowski — announced this week they will oppose DeVos’ confirmation. That left opponents needing only one more Republican vote to block the longtime champion of charter schools and Republican donor.

Toomey has tried to quell any possibility that he’ll be that vote, telling reporters, “I don’t know where the mystery came from. I’m a big fan of Betsy DeVos. I will absolutely be voting for Betsy DeVos.”

He reiterated his support in a statement that said she has “worked for children, parents and teachers to give low-income children the chance to escape crime and poverty. And, let’s face it, too many students are not getting that chance. Their families cannot afford tuition for a private school. Nor can they afford to move to a more affluent neighborhood with a good public school.

“She understands that reform should begin with parents and communities,” he said.

Toomey supported DeVos again when the Senate passed a procedural motion Friday setting up her confirmation vote – perhaps as early as Monday night.

With all other Republicans expected to vote for DeVos, and all Democrats opposing her, Vice President Mike Pence is likely to cast the tie-breaking vote in her favor.

DeVos’ nomination has infuriated progressives and teachers unions, who’ve have jammed the phone lines to Toomey’s office at the Capitol.

“It’s been impossible. I’ve never faced anything like it before,” said Michael Morrill, executive director of Keystone Progressive, of trying to get through to Toomey’s office.

Morrill’s group, like other opponents of DeVos, fear she’ll reduce funding for public education in favor of the charter schools that she has championed as head of the American Federation for Children.

Wythe Keever, a spokesman for the Pennsylvania State Education Association, said that after being unable to get through to Toomey’s office, he “dusted off” his fax machine for the first time in years and weighed in Thursday.

Toomey’s statement backing DeVos hasn’t deterred protests.

Members of the American Federation of Teachers demonstrated outside a Toomey fundraiser in downtown Philadelphia Thursday night.

Others with Morrill’s group protested outside a Delaware County Republicans event hoping to get a glimpse of Toomey.

The state education association is planning a rally in Media, Pennsylvania, on Sunday.

DeVos, though, has had strong backing from conservative groups who’ve been pushing her nomination.

Americans for Prosperity, backed by billionaire industrialists Charles and David Koch, thanked Toomey for his support and called DeVos “a champion for school choice and common-sense reforms that increase education outcomes. “

The group spent $13 million opposing Democratic candidates in last year’s election, including $2.4 million for ads against Toomey’s opponent, Katie McGinty.

A Toomey spokesman said in a statement Friday that his staff has been emptying its voicemail regularly – only to have their inboxes quickly fill up again.

The staff is taking “all hands on deck” approach to answering calls and emails, in addition to its regular work, the statement said. Toomey gets a daily summary of the calls and emails.

In opposing DeVos, Murkowski and Collins raised similar concerns as those of her opponents – that she is unqualified to improve public schools.

Murkowski said DeVos “has been so involved in one side of the equation – so immersed in the push for vouchers – that she may be unaware of what actually is successful in the public schools, and what is broken, or how to fix them.”

Collins said DeVos “appears to view education through the lens of her experience in promoting alternatives to public education. … Her concentration on charter schools and vouchers, however, raises the question of whether or not she fully appreciates that the secretary of education’s primary focus must be on helping states and communities, parents, teachers, school board members and administrators strengthen our public schools.”

Supporters, however, say DeVos and her emphasis on charter schools will shift power over education from the federal government to states and parents.

Sen. James Lankford, R-Okla., in a speech Friday on the Senate floor, decried “the dangers of a centralized, one-size-fits-all bureaucracy that assumes every child learns the same way and requires the same school model.

“I want Oklahomans, not bureaucrats in Washington, to address our education needs, because they can make education decisions that are best for Oklahoma students, teachers and families,” he said.

Kery Murakami is the Washington, D.C. reporter for CNHI’s newspapers and websites. Contact him at kmurakami@cnhi.com