I have always been of the mind that the GOP needs to win the argument and not restrict immigration South of the border just because the Democrats are better at campaign messaging. However, that does not necessary mean that we should blatantly ignore policy implications from immigration reform proposals.
Heritage has taken the lead on this issue from the conservative point of view, and the data are worth a law to be sure.
Encouraging Lawful Immigration and Discouraging Unlawful Immigration.