Sorry if this has been posted previously, but thought you may want to read CFR's take on the candidates' immigration stances and history:
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Council on Foreign Relations
The Candidates on Immigration
Updated: December 6, 2007

Democratic Candidates
Joseph Biden, Jr.
Hillary Clinton
Christopher Dodd
John Edwards
Mike Gravel
Dennis Kucinich
Barack Obama
Bill Richardson

Republican Candidates
Sam Brownback
Rudolph Giuliani
Mike Huckabee
Duncan Hunter
John McCain
Ron Paul
Mitt Romney
Tom Tancredo
Fred Thompson
Tommy Thompson


The rise of globalization, combined with growing concerns over security and terrorism, has transformed immigration into an issue with significant foreign policy implications. In the 2006 midterm elections, immigration emerged as a significant issue in a number of campaigns, although it is not clear how decisive a role it played. The importance of a reformed immigration policy in a broader homeland security strategy has made it a major subject of debate in the 2008 presidential election. This debate escalated recently surrounding the controversial immigration reform legislation that would have granted temporary guest status to millions of illegal immigrants. That bill stalled in the Senate June 7, 2007 after a cloture motion was rejected, although nearly all of the presidential candidates currently serving as senators voted for that motion.

Democratic Candidates on Immigration
Joseph Biden, Jr.

Immigration is not listed as a priority issue on the campaign website of Sen. Biden (D-DE). As chairman of the Senate Foreign Relations Committee, Biden has focused efforts on the problems in Iraq. He said in November 2006 that Mexico’s corruption, inequality, and its “erstwhile democracyâ€