One more thing about this. Apportionment of House seats depends on number of residents, not number of citizens. So, even with perfectly secure elections, adding a bunch of illegals to a state means more representation in the House. Thus, control of the House of Representatives can be affected by the population of illegals, which in turn affects legislation at the federal level — all without any conventional election fraud whatsoever. That means it also affects the number of electors in the Electoral College: election of the president.
The whole point of mass illegal migration is to change the outcome of elections even without the usual election fraud. Realistically, there will continue to be election fraud in Democrat-run states for a long time. Removing the illegals is a way to partly circumvent this problem.