IMO it's all about votes.
That cheap labor costs us more than 2-3 three legal citizens combined. That cost is welfare, hospital closings, medical cost, auto insurance cost, our gasoline prices, electricity cost, theft prevention, gang units, police overtime, the price just continues to grow!
When do we say enough?
Lots of talk in my red state about being upset with just about everything. If things don't improve soon, people here will select whatever candidate with the most common sense promises to fix the current problems (including immigration). Politicians not taking steps to curb the flow of illegals and put a stop to their taking of our benefits are going to be in for a rude awakening when they come up for re-election. Like our jobs and our benefits, there will be no security for pork-barrel - give away the store politicians either. Wake up call for both parties!