The recent firing of Veterans Affairs Secretary David Shulkin sets up a moment of truth for Sen. Dean Heller on whether to back President Donald Trump’s nominee to head the troubled agency despite growing concerns over his qualifications.

Heller has, so far, been silent on Trump’s decision, announced Wednesday evening on Twitter, to fire Shulkin in favor of Ronny Jackson, who is the president’s physician. Heller’s office did not respond to a request for comment.

But, as a member of the Senate Veterans Affairs Committee, Heller will be forced to weigh in on Jackson when the panel considers the nomination prior to the full Senate vote.  

The nomination highlights Heller’s difficult path to get re-elected in a state Trump lost to Democratic presidential nominee Hillary Clinton. Heller must embrace the president in order to keep the backing of the GOP base, while not turning off the independent voters he may need to win the general election, which is expected to be decided by only a few percentage points.

The race has garnered national attention, with Vice President Mike Pence stumping for Heller in January and set to make another visit to the state in April. The outcome could decide control of the U.S. Senate, where Republicans hold a razor thin 51 to 49 majority over Democrats.

A reliable vote for Trump and Senate Republican leaders on White House nominations, including supporting Shulkin and the 21 other members of the president’s cabinet, Heller has campaigned as a champion of veterans. The Jackson nomination may test that claim.

Some veterans groups are concerned whether Jackson, who is a doctor, but does not have any experience running a large agency or company, is qualified to run one of the federal government’s most complicated agencies.

“What we know, from nearly almost a century of experience, is that it takes a deep understanding of the needs of America’s veterans and considerable management skills to run such a large bureaucracy,” Joe Plenzler, director of media relations of the American Legion said Friday.

“The Department of Veterans Affairs is a massive enterprise,” Plenzler continued. “It’s the nation’s second largest bureaucracy, with a budget of nearly $200 billion, more than 360,000 employees, over 170 hospitals and more than 1,000 clinics.”

There are more than 200,000 veterans in Nevada, according to the Veterans Administration (VA), including more than 100,000 enrolled in the VA health-care system. More than 40,000 receive disability compensation, and more than 6,000 receive education benefits under the G.I. bill. More than 40 percent of the state’s veterans are 65 or older, more than 30 percent of whom served in Vietnam, according to the U.S. Census Bureau.

Management at the VA has been a concern for Congress, due in part to a backlog in benefit claims, which has resulted in veterans dying before being able to get care.

The decision to nominate Jackson caught most veterans advocates by surprise, leaving the groups unsure about whether the nominee was the right person for the job.

“That’s a question best asked of the U.S. Senate,” said Plenzler, who noted that the American Legion does not endorse nominees.

“Nobody’s heard of this guy other than him being the president’s physician,” Plenzler added. “We found out through the media just like everyone else that this was the president’s. We don’t have any prior experience with the nominee, but we do want to meet with him, at the earliest opportunity, to discuss his thoughts on the direction of the department and we stand ready, as we often do, to offer our best advice to this administration on what the needs of America’s veterans are.”

The Veterans of Foreign Wars also have reservations about Jackson’s background.

“Dr. Jackson’s bio does not reflect any experience working with the VA or with veterans, or managing any organization of size, much less one as multifaceted as the Department of Veterans Affairs, so the VFW will be closely monitoring his Senate confirmation process,” the group said in a statement.

Jackson, an admiral, has served as a White House physician since 2006, beginning under President George W. Bush. He was appointed the president’s physician by President Barack Obama.

“Since arriving at the White House, he has directed the Executive Health Care for the President’s Cabinet and Senior Staff, served as physician supervisor for the Camp David Presidential Retreat, held the position of physician to the White House and led the White House Medical Unit as its director,” according to his Navy bio.

He is best known for announcing the result of Trump’s physical in January when he declared that the president was in “excellent” health.

Other Senate Republicans were also caught off guard by Jackson’s nomination. Georgia Republican Johnny Isakson, who is chairman of the veterans panel, praised Shulkin upon hearing of the decision, but had little to say about Jackson.

“I thank Dr. Shulkin for his dedicated service to our country and our veterans,” Isakson said in a release. “I look forward to meeting Admiral Jackson and learning more about him.”

Shulkin, who was a holdover from the Obama administration, had been under increased scrutiny for a 2017 trip to Europe to which he brought his wife, paid for by taxpayers. An inspector general report issued in February found that the VA improperly paid for his wife’s trip.

Shulkin also clashed with Trump administration officials over their push to privatize health care at the VA. “They saw me as an obstacle to privatization who had to be removed,” Shulkin wrote in an op-ed in The New York Times on Wednesday.