Story highlights 1 in 8 who identified as Republicans or Republican-leaning in November 2016 no longer do so

no longer do so This marks the widest Democratic advantage since Obama took office in 2009

Washington (CNN) Since last year's presidential election, some Republicans have been running for the hills.

of Americans self-identify as Republicans or Republican-leaning independents during 2017 so far, Only 38%of Americans self-identify as Republicans or Republican-leaning independents during 2017 so far, according to an average of monthly numbers from Gallup . This number marks the lowest it's been in more than a quarter century of polling, stretching back to 1991.

Over the last year, the polling data shows the GOP share of the electorate falling from a 42% monthly average around the presidential election in November 2016 down to a 37% monthly average now, one year later.

That also means roughly one in eight people who identified as Republicans or Republican-leaning in November 2016 no longer do so. (The number of Democrats has held roughly steady over the same period.)

Meanwhile, an average of 45% of the US population says they identify as Democrats or Democratic-leaning independents in 2017 so far. The gap between Democrats and Republicans marks the widest Democratic advantage in the electorate since former President Barack Obama took office in 2009.

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