US deaths are also rising and have recently reached the highest levels since early June, led by Arizona, California, Florida and Texas, according to the tally.
More than half of all states - 30 out of 50 - have reported record one-day increases in cases this month. Infections are rising in almost all states, based on a Reuters analysis of cases the past two weeks compared with the prior two weeks.
If Florida were a country, it would rank fourth in the world for the most new cases in a day behind the United States, Brazil and India, according to a Reuters analysis.
Americans have become increasingly divided on issues such as the reopening of schools and businesses and wearing face masks in public. There is near-universal consensus among health experts that wearing masks is one of the most effective ways to stop transmission of the virus, which has killed more than 134,000 Americans.
The current tally of 75,255 cases surpasses the previous record was set on Friday when cases rose by 69,070. In June, cases rose by an average of 28,000 a day, according to a Reuters tally. In July, they have risen by an average of 57,625 a day.
Dr. Anthony Fauci, the government's top infectious diseases expert, has warned that cases could soon top 100,000 a day if Americans do not come together to take steps necessary to halt the spread of the virus.