McCain's primary contender, former Congressman J.D. Hayworth, has drawn support from Tea Party activists, backed the bill and chided McCain for not supporting it. Soon after, McCain came out in support of the recently enacted Arizona immigration legislation.
McCain always said border security was a precondition to any plan that would give citizenship to illegal immigrants and he has not changed his position on naturalization, said Dan Schnur, a former advisor to McCain in his 2000 presidential campaign and now a professor at UC Berkeley.
Schnur said McCain's change in policy had to do with political pressure he was receiving from conservative elements in his party, but also had a lot to do with the reality of the situation in Arizona, where illegal immigration has spiked in recent years.
"Some of it has to do with type of primary that he's facing. But there is also been a fairly substantial change in the real world situation in Arizona," said Scnur. "There is no question that political pressures have had some impact, but just as great an impact has been a result of the on-the-ground situation."
Some conservative analysts do not see McCain's change in policy as a reversal, or a kowtow to the Tea Party but in keeping with his long-standing strategy to be a maverick.
"It ain't front page news that Sen. McCain shoots from the hip and is impulsive. Remember he picked Sarah Palin for his running mate," said former George W. Bush advisor and Republican strategist Matthew Dowd.
"Also, keep in mind this doesn't represent the influence of the Tea Party since every poll in Arizona and nationally shows Americans are longing for secure borders and support what Arizona did because they don't trust the federal government," Dowd said.