The same as it has always been for the Republicans...DIRT CHEAP LABOR!
With the added "benefit" of driving down wages for law-abiding, tax-paying Americans.
The Rat party OTOH, wants the illegal flood across the Mexican/US border to continue because they are natural demoRat voters.
So you see because both parties want them they will NEVER really do anything that would stop the Mexican takeover of the southwestern USA.
To quote Texas Dawg "We are doomed!"
I guess the GOP has done a pretty lousy job of achieving this "goal" of theirs. Wages and real disposable incomes in America have done nothing but rise, across-the-board, for the past 2 decades.