A vice-presidential debate of unprecedented importance but few fireworks concluded in Salt Lake City, Utah on Wednesday evening with Republican Mike Pence and Democrat Kamala Harris sparring on COVID-19, the economy and healthcare.

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The candidates sat 3.7 meters apart with plexiglass screens between them, a visual reminder of the ongoing pandemic that has killed more than 210,000 Americans and the COVID-19 outbreak in the White House, and both repeatedly avoided directly answering questions from moderator Susan Page, USA Today's Washington bureau chief.

With Joe Biden extending his national lead over Donald Trump in the past week according to CGTN analysis and edging further ahead in battleground states, the clash was an opportunity for Pence to make a case to reverse the Republican slide in the race for the White House – but with no knockout blows or gaffes on either side, it's unlikely to move the polls.

The head to head was a much more constrained affair than the first presidential debate, though Pence repeatedly spoke over moderator Page, exceeded his allotted time and interrupted Harris, who regularly said "Mr Vice President, I'm speaking." 

The highlight of a low-key debate for many online was the sight of a fly perching on Pence's head; Biden immediately tweeted a photo of himself with a fly-swatter and "Pitch in $5 to help this campaign fly."

COVID-19 dominates

Pence, the vice president and the head of the White House's task force on COVID-19, sought to defend the Trump administration's handling of the pandemic, saying "from the very first day, President Trump has put the health of America first."

"Whatever the vice president is claiming the administration has done, clearly it hasn't worked," Harris, who generally played it safe, shot back, adding Trump and Pence have "forfeited their right to reelection."

The 55-year-old California senator, the first Black and first Asian American to be a running mate on a national ticket, began the debate by saying the White House's handling of the COVID-19 pandemic was "the greatest failure of any presidential administration in the history of our country."

Harris later accused the administration of not being straight with the American people about the virus. "They knew what was happening and they didn't tell you," she said. "They knew and they covered it up."

Pence, the 61-year-old former radio host, went on to say the Biden plan for tackling the pandemic "plagiarized" the approach taken by the Trump administration, before taking a dig at the former vice president's lifting of sections of a speech by former British politician Neil Kinnock during his 1988 bid for the White House. 

"I mean, quite frankly, when I look at their plan, that talks about advancing testing, creating new PPE, developing a vaccine, it looks a little bit like plagiarism, which is something Joe Biden knows a little bit about," Pence said.

He went on to accuse Harris of undermining trust in a vaccine by saying she would only take one approved by scientists, not by Trump. 

Other business

The debate featured the running mates to a 74-year-old Republican president undergoing treatment for COVID-19 and a 77-year-old Democratic nominee – for both Pence and Harris showing a readiness to step into the top job was a key task, and both gave measured performances avoiding major mistakes.

Harris, who has been on the national stage as a senator for just four years, set out her biography as she sought to introduce herself to the country and demonstrate her capacity to serve as an understudy to a President Biden. 

Both candidates avoided answering a question about whether they had discussed succession with their running mates. 

In The Spotlight:

Mike Pence: Working in Trump's shadow

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On policy, Harris made a powerful to-camera statement on healthcare, noting that the Trump case is pursuing a court case to abolish the Affordable Care Act.

"If you have a pre-existing condition, heart disease, diabetes, breast cancer, they're coming for you," the Democrat warned. "If you love someone who has a pre-existing condition, they're coming for you." The vice president avoided answering how pre-existing conditions would be protected in a second Trump term. 

Pence tried to pin Harris on court-packing, the idea promoted by some Democrats of increasing the size of the Supreme Court to negate an expected 6-3 conservative majority, a question which the Democrat refused to directly answer. 

The Republican touted the move of the U.S. embassy in Israel to Jerusalem and the Trump administration's record on ISIL as successes on foreign policy, while Harris talked up the importance of building relationships around the world. 

The candidates also clashed over taxes, with the vice president claiming that a Biden administration would raise taxes on everyday Americans and Harris insisting that no one earning under $400,000 would pay more if the Democrat is elected. 

Harris also hit out at Trump's minimal personal tax payments and noted that he reportedly owes $400 million in loans.

On climate change, Pence said he was "very proud of our record on the environment and on conservation" and repeatedly said a Biden-Harris administration would ban fracking, a claim the Democrat flatly denied. 

With the debate unlikely to lead to a major shift in the race, eyes now return to the top of the ticket and prospect of a second presidential debate on October 15. 

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