Here's my guess: there are lots of datacenters being built in Virginia, Pennsylvania, Indiana, Ohio, Illinois [1]. Also in Texas, Georgia, Arizona, Nevada and Utah.
I think the first 5 states have this in common: there are lots of coal burning power plants that were shut down, but can be restarted and hooked to the grid on a relatively short notice. The grid is also quite good in this region.
In Texas, it is likely that new power can be generated with a combination of solar, wind, gas, and fast permitting.
I don't have an explanation for Georgia.
For Arizona, and perhaps Nevada and Utah too, I think it is likely to be solar.
[1] https://www.axios.com/2025/12/18/data-center-growth-map-stat...