(CNN) With traditional campaigning abandoned and the Democrats' presidential front-runner hunkered down at home, deep-pocketed Democratic groups are racing to hit President Donald Trump over his response to the coronavirus pandemic.

The groups have gone on the offensive on the premise that the pandemic likely will shape the remainder of the 2020 campaign and how voters judge Trump and other Republicans. But the ramped-up spending also has sparked debate among strategists over whether voters are open to attacks on the President as Americans confront the biggest public health emergency of their lifetimes.

"This crisis could be the defining issue of this election," Kyle Tharp, of the nonprofit group Acronym, said Wednesday. "Now more than ever, voters need to be made aware of how Trump's handling of this threat and downplaying of its impact has made it worse and has made Americans less safe."

Through its super PAC arm, Pacronym, the group is spending $2.5 million through April on coronavirus-related ads with plans to double that by July.

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