[NobleFree]

If too many individual purple states (if it happened in a red state that would be surprising) each changed their laws to allocate electors based on the national popular vote that would be very dangerous. And they would not need a US Constitutional amendment to do it.

Correct - the only Constitutional issue is states entering into a compact to do so. But there's no evidence that even the blue-est state is willing to so decide without a compact.

[ding_dong_daddy_from_dumas]

A blue state allocating electors proportional to the national popular vote would tend to lose electoral votes for the dems. A blue state giving all its electors the the winner of the national popular vote would not change the electors for that state. Maine switching to winner-take-all based on either the national, or statewide popular vote might make a small difference.

The danger is that the red and blue states keep their current systems but the purple ones change to winner-of-the-national-popular-vote-take-all. I expect the big metro areas to keep getting bigger and voter fraud to get worse.