Poll shows Hillary Clinton with a growing lead in a state that's turned blue only once since 1948

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(Hillary Clinton.Joe Raedle/Getty Images)

Hillary Clinton has a growing lead in Arizona — a state that has voted for a Democratic president just once since 1948.

A Wednesday poll from The Arizona Republic showed Clinton with a 5-point lead over Donald Trump in a four-way race that included Libertarian nominee Gary Johnson and Green Party nominee Jill Stein.

The Democratic nominee held a 39% to 33.9% advantage over the Republican nominee in the poll. When undecided voters leaning toward either candidate were included, those numbers increased to 43.3% for Clinton and 37.8% for Trump.

In a late-August Arizona Republic poll, Clinton's lead over Trump was just 1 point.

After the poll's publication, Clinton swung into a slight lead in the RealClearPolitics polling average for the state. She now leads the Manhattan billionaire by 0.2 points.

The last Democrat to win a presidential race in Arizona was Clinton's husband, Bill, in 1996.

The poll's margin of error was plus or minus 4.3 percentage points.

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