Serious people measure death rates, not "cases". Cases is pretty arbitrary.
If you want, you can do serological studies to estimate the proportion of a population that was infected, but please don't think there is any value to "cases", and serological studies are generally done after a disease is over, because diseases hit different areas in different times. They spread over time, going from place to place, so one area with a low infection rate may simply not have been hit yet. A great example of this is Singapore, which everyone thought had licked the disease, when in reality it was just hit later. Similarly everyone was blaming New York, but even though New York made some mistakes with nursing homes, it's biggest crime was to be one of the places hit first. Similarly, after the disease burned through New York and started growing in Arizona, that didn't mean that suddenly New York had better policies than Arizona. That's why you wait until everything is over and then you do serological studies before jumping to conclusions.
FYI lowest death rates (as of 3 days ago) are Vermont, Maine, Alaska, Hawaii. Hawaii is a bit of an outlier as it is an island that for a while had strict protocols limiting visitors. I suspect Hawaii merely delayed its day of reckoning, similar to Australia or New Zealand, but I could be wrong. Time will tell.
Highest death rates are Mississippi, New Jersey, New York, Louisiana, Alabama.
Massachusetts has a higher death rate than Florida. Does that mean it has worse policies? No you can't conclude that, it just means there are a lot of confounding variables and you can't conclude efficacy of policies like that. California has a higher death rate than Utah, does that mean it has worse policies? No, you can't conclude that either. That's not how you do science.
https://www.statista.com/statistics/1109011/coronavirus-covi...
We'll need to wait until it's all over to get the final tally. Then we can also do serological studies to determine extent of infection.