A new poll shows Arizona Sen. John McCain widening his lead over his Republican challenger ahead of next month's GOP primary.
The Rocky Mountain Poll released Wednesday shows McCain leading former U.S. Rep. J.D. Hayworth 64 percent to 19 percent. Political newcomer Jim Deakin had 5 percent.
McCain's margin has widened from a 54 percent to 28 percent lead he held over Hayworth in the same poll in April.
The telephone poll was conducted by the Behavior Research Center between June 30 and July 11 and has a margin of error of plus or minus 5.4 percentage points. Pollsters surveyed a random sample of 334 registered Arizona voters, including 190 Republicans and 144 independents who said they would vote in the Republican primary.
Hayworth spokesman Mark Sanders says the polling firm has "no credibility."
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