The US recorded 3,124 Covid-19 deaths on Wednesday - its highest one-day total yet.
It comes as new cases per day reach an all-time highs of more than 209,000 on average, while at least 106,000 people remain in hospital with the virus, according to the latest figures from Johns Hopkins University.
Coronavirus has so far left more than 290,000 Americans dead.
Wednesday’s death toll eclipsed American deaths on the opening day of the Normandy invasion during World War II when 2,500 out of some 4,400 allied soldiers were killed.
The daily Covid death figure also surpasses the number killed in the terror attacks on September 11, 2001, when 2,977 lost their lives.
The grim figures make all the more pressing a decision from the US medicines regulator on whether to approve the Pfizer/BioNTech Covid vaccine already being rolled out in the UK.
The Food and Drug Administration met on Thursday to discuss if it would sign off the jab for use in the US.
Depending on how fast that decision is made, a vaccination programme could begin across the US in a matter of days - marking the start of the biggest vaccination campaign in the country's history.
On Wednesday Canada became the third country in the world to approve the Pfizer jab - behind Britain and Bahrain.