McCain: In 2006, McCain co-sponsored the Senate immigration bill that would have legalized millions of immigrants in the U.S., strengthened border control and created a guest-worker program. As a presidential candidate, he has since said he believes in securing the borders before legalizing immigrants. He also backs what he calls a "sensible" guest-worker program for workers who are in the country without legal status and has callled for strengthening penalties for those who hire undocumented immigrants.
Obama: Obama voted for the Senate immigration overhaul bill to strengthen border controls, create a guest-worker program and legalize millions of foreign workers here now. Obama also backed the Secure Fence Act. He co-sponsored a bill to allow states to offer illegal immigrants in-state tuition.
Illinois Sen. Barack Obama was part of a bipartisan coalition of senators to work on an immigration bill. He stands outside the White House, after meeting with President George W. Bush on April 25, 2006, to discuss the bill that stalled in the Senate.
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Republican Sen. John McCain joins Democratic Sen. Ted Kennedy (right) at a Capitol Hill press conference on revamping immigration, Sept. 26, 2006.
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In recent years, public debate over illegal immigration has been passionate, divisive and loud, and it has provided plentiful fodder as a wedge issue for politicians, especially Republicans.
But there has been virtual silence on the topic on the presidential campaign trail.
"This is no disrespect to the candidates, but their positions are as distinct as Tweedledum's from Tweedledee's," says immigration lawyer Angelo Paparelli.
It is an irony that Arizona Republican John McCain is the presumptive presidential nominee for the party that has most ardently waged war against illegal immigration. In 2006, McCain co-sponsored the bipartisan McCain-Kennedy immigration bill — also supported by Illinois Sen. Barack Obama.
The bill would have stepped up enforcement at the border and in the workplace. It also would have expanded guest-worker programs and, most controversially, legalized millions of undocumented immigrants already in the U.S. if they paid fines, paid back taxes and learned English.
McCain's conservative colleagues derided the bill as "amnesty" and helped foment a grass-roots backlash. By 2007, as McCain was gearing up for his presidential bid, he backed down. When the Senate crafted legislation that year, he was nowhere to be seen, and some critics fault his absence for the bill's eventual failure.
In January of 2008, when NBC's Tim Russert asked McCain if he would support his own immigration bill if it came to him as president, McCain rejected the notion.
"It isn't gonna come," he said. "The lesson is, they want the border secured first. That's the lesson."
McCain now says he would have Southwest state governors first certify the border was secure before expanding any legal visas. But not everyone is convinced by the tougher talk.
"John McCain is emotionally invested in amnesty for illegal immigrants, period," says Steve Camarota of the Center for Immigration Studies, which advocates less immigration.
Camarota believes either a President McCain or a President Obama might temper some of the more aggressive immigration enforcement of the Bush administration. In an interview last year with the editorial board of The Des Moines Register, Obama spoke about a different approach to workplace enforcement.
"I'm not particularly impressed with raids on plants that grab a handful of undocumented workers and send them home, leaving the company in a position where it can just hire the next batch," Obama said. "I don't think we've been serious about employer sanctions."
Still, immigration lawyer Paparelli doubts either McCain or Obama would make immigration a priority as president, at least not early in a first term.
"Immigration has been described as the third rail of American politics," Paparelli says, "but more vividly by some as a downed power line that anyone who touches it will be electrified."
Presidential Candidates' Key Immigration Advisers
Juan Hernandez, the adviser to Mexican President Vicente Fox for Mexicans abroad, speaks while touring a new factory on July 6, 2001, in Mexico. He now advises Arizona Sen. John McCain on immigration.
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A former U.S. secretary of both transportation and energy, Federico Pena advises Illinois Sen. Barack Obama on immigration. Pena served in former President Bill Clinton's administration.
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Republican Arizona Sen. John McCain: McCain's Hispanic outreach director is Juan Hernandez, who is also a passionate advocate for migrants' rights. Hernandez became the first U.S.-born member of Mexico's cabinet when former President Vicente Fox appointed him as head of the President's Office for Mexicans Abroad. Hernandez's position with the McCain campaign has generated controversy on conservative blogs. McCain was asked about Hernandez's role in the campaign at a town hall meeting in January 2008.
According to the campaign Web site, McCain also has appointed an advisory board to counsel him on issues important to Hispanics. Its members are primarily from Florida, New Mexico, Colorado and Arizona.
Democratic Illinois Sen. Barack Obama: Obama is being advised about immigration by three academics at the University of California-Davis School of Law who focus on immigrant rights and social justice. Associate Dean Kevin Johnson has argued that more open borders would be better for the economy and national security. The other advisers are Bill Hing, a professor of law and Asian-American studies, and acting professor Jennifer Chacon.
According to Obama's campaign, he also receives immigration advice from former U.S. Secretary of Transportation and Energy Federico Pena, Stanford Law School professor Mariano-Florentino Cuellar, Arizona Gov. Janet Napolitano, and New Mexico Gov. Bill Richardson, himself a former candidate for the 2008 Democratic presidential nomination.