Poll: GOP ahead in Arizona Senate race

But 23 percent of Democratic voters are undecided, compared to 14 percent for Republicans, who are already familiar with Flake. That could give Democrats a chance to define their candidate on their terms once the primary comes to a close.

The poll of 743 primary voters was conducted Feb. 17-19 using automated telephone interviews and had a margin of error of 3.6 percentage points.

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