That law, which called on police officers to check a person's immigration status when enforcing unrelated laws, also played a big role in Brewer's 2010 campaign. In fact she experienced in a big turnaround in large part because of it. By signing the law, she cleared the Republican primary field, making quick work of well-funded and well-known Republicans who appeared poised to defeat her.
Brewer used that momentum as a springboard into the general election. She handily defeated state Attorney General Terry Goddard (D), who also initially seemed to be a formidable opponent. The Brewer-Goddard contest may not have matched the tension in the race between Giffords and Kelly in the 8th Congressional District, but it had its fervent moments.
Goddard was heavily critical of Brewer over comments she made about beheaded bodies being found in the desert. The claim was unsubstantiated, and eventually Brewer backtracked, but the grim image left its mark on the race. Goddard was also critical of illegal immigration, but did not favor the controversial immigration law, instead advocating for a focus on drug cartels as an effective way to address illegal immigration.
But for Brewer and Goddard, the external immigration threat and frustration at the lack of assistance from the federal government on the issue seemed to cross party lines. Both candidates spoke regularly of the need for greater border security, but offered different remedies.
The immigration law also had an impact on the Senate contest, in which Sen. John McCain (R-Ariz.), who once toed a more moderate line on the issue, faced a much more conservative candidate in former Rep. J.D. Hayworth (R-Ariz.).
Recognizing how conservative the Arizona Republican primary electorate was on the issue, McCain pivoted hard to the right and embraced the measure. In one of the more memorable TV ads of the cycle in Arizona, McCain urged law enforcement to "complete the danged fence" along the border with Mexico.
The immigration law permeated other races as well and, in some cases, led to violence. In July, someone shattered a window in Rep. Raul Grijalva's (D) office. Grijalva had called for visitor boycotts of Arizona to protest the immigration law.
"There isn't anything in Arizona that's uniquely different," said Giffords's predecessor in the House, former Rep. Jim Kolbe (R-Ariz.) on ABC's "Top Line" earlier this week. "We have been the epicenter of the illegal immigration, and the frustration of people about that has been tremendous. There's no question about that. And I agree with the sheriff when he said that our political discourse needs to be cooled down, we need to lower the tone."
"But," he continued, "I think it's a tremendous mistake to link that to this particular incident, which seems to be an incident caused by or undertaken by a seriously deranged young man and doesn't seem to have any kind of connection to a specific political issue."