Defining Congressional Districts, using Software

This could be done fairly easily.

Voting is always done in voting precincts. These precincts always have boundaries with adjacent precincts. And these boundaries are well-known, and are easily defined - a simple matter of geometry.

The first step would be to record how each precinct voted in the last election. And assume it would vote similarly in the next election. If it was Red in the last election, it will probably be Red in the next election.

This would not work very well, if the most of the voters decided on another alternative entirely. As happened in the election of Trump. But the votes would still be counted, precinct by precinct.

If most of the precincts around that precinct, voted the same way - merge these precincts together. Otherwise leave them separate. Repeat this process until all the precincts in the State have been considered.

The next step would have to be done by people - who would have to decide how to proceed from there. If too many separate precincts remain - they will have to decide on a plan to reduce them. They might decide, for example, if 40% of the surrounding precincts have voted one way - to merge them.

And they will have to decide if non-contiguous voting areas could still vote as one area. This has not been a common practice before now, in most countries - but it might work.