It's a long article.  I'll just post the premise and the link: http://www.nationalreview.com/articles/286981/gop-candidates-betray-spirit-reagan-immigration-daniel-griswold

Immigration has loomed larger as an issue in the Republican presidential debates than it does in the minds of most voters. Driven by a minority of activists in their party, the candidates have been drawn into an unhealthy competition to see who can sound the harshest in cracking down on low-skilled illegal immigrants from Latin America.

So far the biggest loser in the competition is the Republican party.

The party is losing out because the rhetoric brings us no closer to actually solving the problem, while driving away voters crucial to the party's long-term success.