Meanwhile, Arizona's law has sparked efforts in more than a dozen states to pass similar measures and propelled immigration into the spotlight during the 2010 campaign.
Candidates in races across the country have been forced to take sides on the debate, with the issue playing a particularly prominent role in gubernatorial races in states with the highest concentrations of illegal immigrants.
In Florida, Democratic gubernatorial candidate Alex Sink promised to veto a proposed immigration law similar to Arizona's if it were to pass, while Republican Rick Scott has offered a conditional endorsement.
California Republican Meg Whitman, who's faced intense scrutiny for having employed an undocumented worker, has said she opposes an SB 1070-like law in her state but has tried to push a tough line on illegal immigration.
Nikki Haley, Republican gubernatorial candidate in South Carolina and daughter of Indian immigrants, has promised to enact an "Arizona-style" immigration law if she's elected. Her opponent, Vincent Sheheen, says he would not.
In New York, Republican gubernatorial candidate Carl Paladino has said he supports Arizona's right to impose a strict immigration law and would direct state law enforcement to crack down on illegal immigrants. His Democratic opponent, Andrew Cuomo, opposes such measures.
Brewer, a Republican who is up for re-election on Nov. 2, has been leading her Democratic opponent, state Attorney General Terry Goddard in polls. Goddard opposes SB 1070.
Sixty percent of Americans support the Arizona law, according to the most recent ABC News/Washington Post poll. But fewer -- 46 percent -- think the states should have power to make and enforce their own immigration laws, one criticism of the Arizona statute.