WASHINGTON — Coronavirus is already coloring the 2020 campaign, with Democrats convinced President Donald Trump’s response to the outbreak leaves him and down-ballot Republicans vulnerable over the burgeoning health crisis, his competency and — potentially most damaging — the staggering economy.

Republicans are fighting back by accusing Democrats of politicizing the fight against the virus and COVID-19, the sometimes deadly disease it causes. But mostly, a nervous GOP is hoping administration actions will reverse the stock market’s nose-dive, avert a recession and control the coronavirus in just a few months.

That could allow time to prevent the problems from becoming Trump’s Hurricane Katrina and defining November’s election battles for the White House and Congress. President George W. Bush was harshly criticized for his administration’s belated handling of the deadly 2005 storm, which battered New Orleans, damaged his presidency and contributed to the GOP’s loss of House control the following year.

“The economy has been his whole shtick,” said former Rep. Tom Davis, R-Va., who once headed the House GOP’s campaign committee. “If the market tanks and the economy goes down, I think Trump’s whole reason for being in office goes away.”

People in both parties say a recession and rampant disease outbreak would cripple Trump’s reelection and Republican efforts to capture House control and defend their Senate majority. That’s an edge Democrats are primed to exploit.

“Every elected @GOP official owns this moment,” Rep. Sean Casten, D-Ill., tweeted last week after Trump delivered a prime-time national address that erroneously described several steps he’s taking to try containing the virus. “They elected him. They coddled him. They cowered before him.”

Republicans say there is still time for Trump to tame the coronavirus and the economy and consign them to background noise before Election Day.

“If we do this right, in the midsummer the economy and stocks will come roaring back,” said Rep. Steve Stivers, R-Ohio.

“You wouldn’t have had a massive fluctuation in the stock market (last) week if he wasn’t really disturbing the confidence of investors,” said Rep. Debbie Wasserman Schultz, D-Fla., a former Democratic Party chairwoman. She said Trump’s “fly by the seat of his pants, cover his own tuchus approach does not inspire confidence.”

Democratic presidential candidates have struck similar themes.

Former Vice President Joe Biden said “a pervasive lack of trust in this president” had hindered the response to the virus, compounded by Trump’s leaving the country “woefully unprepared.”

Biden’s chief rival, Vermont Sen. Bernie Sanders, said the administration’s “incompetence and recklessness have threatened the lives of many, many people.”

Biden and Sanders are scheduled to debate each other Sunday night.

Rarely has a debate been so shaped by palpable anxiety: The event has been relocated from a Phoenix theater to a Washington television studio to limit any unnecessary travel. There will be no live audience and no spin room. One moderator who had potentially been exposed to the virus has bowed out to avoid spreading it.

“It is going to be a different kind of debate,” Sen. Chris Coons of Delaware, an early ally and surrogate for Biden, said.

The New York Times contributed.