(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.
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"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.
Three other groups also have launched ads against Trump. Priorities USA Action, the largest Democratic super PAC, on Tuesday began a $6 million digital and TV campaign that opens with a commercial, juxtaposing the grim rise in coronavirus cases with Trump's comments downplaying the threat.
American Bridge, another Democratic super PAC, is running Facebook ads that highlight Trump's words about the pandemic and argue that he can't "be trusted with our economy, our health and our future."
The latest coronavirus-related attack on Trump came this week from Unite the Country, a super PAC closely aligned with the Democrat's front-runner for the nomination, Joe Biden. Its seven-figure campaign centers on a 30-second commercial called "Crisis Comes."
"Crisis comes to every presidency. We don't blame them for that. What matters is how they handle it," the narrator says, before saying that Trump "let the virus spread unchecked across America."
The pandemic, which had infected more than 64,000 and killed at least 900 in the US as of Wednesday evening, has upended American life and brought the economy to a halt a little more than seven months before the general election.
The political stakes are high for Democrats and Biden.
Trump, who has dominated the airwaves with daily briefings from the White House, has seen his poll numbers climb -- driven, in part, by his response to the pandemic.
A new Gallup poll shows 60% of Americans approve of Trump's handling of the crisis, while 38% disapprove. A Monmouth University survey shows a tighter margin: 50% say the President has done a good job; 45% say he has done a bad job.
"Poll after poll are coming out with a majority of Americans saying they are supportive of President Trump's handling of the coronavirus," Trump campaign spokeswoman Erin Perrine said in an email Wednesday to CNN.
Perrine called Democrats' ads "disgusting" and a "politicization" of the pandemic.
The Trump campaign late Wednesday afternoon called for television stations to pull down Priorities' ad, contending that language in the commercial asserting that Trump called the coronavirus a "hoax" was false because Trump actually was referring to Democratic criticism of his response to the pandemic.
Some Democrats have warned against the advertising barrage, questioning whether voters are open to attacks on the President in the midst of a public health crisis.
"There'll be plenty of time for voters to judge @realDonaldTrump & his handling of the Coronavirus crisis, including the first weeks when he sent dangerously misleading signals by downplaying the threat," David Axelrod, a CNN contributor and former aide to President Barack Obama, wrote on Twitter as the first round of coronavirus advertising began to emerge last week.
"But now doesn't seem the moment for negative ads," he added.
David Plouffe, another Obama campaign veteran who now sits on Acronym's board, disagreed, saying Democrats "can't disarm."
"Using Trump's own words and actions to remind people of his failures while he tries to rewrite history is essential," Plouffe tweeted.
Biden himself is working to boost his visibility as the country grapples with the fast-spreading virus and the economic woe it has unleashed.
From a quickly assembled studio in the rec room of his home in Wilmington, Delaware, Biden has staged a media blitz in recent days to try to break into the national conversation that has seen governors, such as New York's chief executive Andrew Cuomo, rise to prominence.
On Wednesday, the former vice president's campaign launched a newsletter and said a podcast would soon follow.
Richard Levick, who runs a global crisis communications firm headquartered in Washington, said Democratic groups have to "put a line in the sand" to counter Trump's effort to define the narrative about his response to the pandemic.
But, he said, "More effective than any ad or commercial will be Joe Biden filling a void ... and showing calm leadership that people need right now."