Republican Gov. Jan Brewer holds a slight lead but the race for the GOP nomination for Arizona governor remains wide open, with roughly half of voters surveyed for a new poll undecided about their choice.
The Behavior Research Center survey released Monday found that 51 percent of the surveyed Republicans and independents planning to vote in the Aug. 24 Republican primary were uncommitted.
Of those voters supporting a candidate, 22 percent backed Brewer. Yavapai County businessman Buz Mills followed at 13 percent, State Treasurer Dean Martin 10 percent and Tucson attorney John Munger 4 percent.
The poll was conducted from April 15 to April 25, meaning the bulk of the polling period occurred before Brewer's April 23 signing of a controversial new law targeting illegal immigration — legislation that has spurred a national debate on the issue.
The survey polled 319 Republican and independent voters statewide, and has a margin of error of plus or minus 5.6 percentage points. Arizona permits independents to participate in a party primary of their choice.
Mills, a political unknown before he entered the race, has contributed more than $2 million to his campaign, which has begun television advertising to introduce him to voters.
The polling center said it was evident while the survey was under way that Brewer picked up support among Republicans after she signed the immigration measure.
However, it isn't yet clear whether Republican primary voters will punish or reward Brewer for her championing a proposed temporary sales tax increase to help close state budget gaps, the center said. The sales tax proposal appears on a May 18 special election ballot as Proposition 100.
The survey did not list Maricopa County Sheriff Joe Arpaio among the Republican candidates.
The five-term sheriff for the county that includes most of metropolitan Phoenix announced Monday he would not run for governor. That announcement marked the fourth election cycle since 1998 where Arpaio has flirted with — but ultimately decided against — running for governor.
The Republican nominee is expected to face the presumptive Democratic nominee, Attorney General Terry Goddard, in the November general election.
Associated Press Writer Jacques Billeaud contributed to this report.
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