WASHINGTON, D.C. -- COVID-19 has upended the campaign for U.S. Senate in North Carolina, reshaping campaign events and refocusing the issue at hand.

Democratic challenger Cal Cunningham says more oversight is needed of the federal response to the pandemic. For example, he says, he wants answers about reports that the U.S. shipped several tons of donated medical supplies to China in February - supplies he says are needed stateside.

He also argues that Republican incumbent Sen. Thom Tillis, the man he is trying to unseat, is not doing enough to hold the Trump administration accountable amid the outbreak.

He says President Donald Trump could have done better "with respect to exercising the powers available to the presidency, invoking the Defense Production Act.” That act allows the president to compel companies to produce needed supplies like masks and ventilators.

“I don’t think that there are any set of circumstances under which [Tillis] stands up to this administration and asks the tough questions,” Cunningham said.

The Tillis campaign takes issue with this claim, pointing to, among other things, a letter the senator co-authored to the Trump administration, highlighting the need for additional testing supplies for North Carolina, plus another letter he sent to the Department of Defense asking for clarification on how they are responding to the outbreak.

In a statement, a campaign spokesman accused Cunningham of launching "hypocritical, partisan attacks," saying, “While Cal Cunningham ... plays politics with COVID-19, Senator Tillis will continue to work across the aisle and support Gov. Cooper to ensure that North Carolinians are protected during this uncertain time."

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Regarding the availability of medical supplies, Tillis's campaign spokesman noted the senator believes Congress should take measures to strengthen the domestic supply chain, reducing the dependency on goods from other countries.

Cunningham said the question of supply chains is an "incredibly important piece" of the conversation, saying he has heard from businesses that are asking those questions in light of the outbreak.

On Capitol Hill, Congress is looking to next steps after already approving three major aid packages in response to the pandemic.

Tillis has repeatedly called for additional funding for a small business loan program that was included in the most recent aid package. The so-called Paycheck Protection Program is set to run out of money soon if Congress does not authorize more.

“I believe we need to make sure this money gets to small businesses as soon as possible, make improvements to the program, and reach bipartisan consensus to provide more funding for our small businesses,” Tillis said in a statement Tuesday, noting that he understands the program is not perfect.

For his part, Cunningham says the outbreak underlines the need for improved rural broadband. He also pointed to rural hospitals and small businesses as two areas in need of additional assistance.

“I hear a lot from small business people who are making difficult decisions about keeping their people employed right now. So, I think Congress is going to need to act on that front,” he said.