Once known as a GOP stronghold, Montgomery County has this year delivered more Democratic presidential votes than almost any other county in Pennsylvania, write Katie Meyer and Ryan Briggs for the WHYY.

The shift has been gradual and somewhat unexpected. When Marcel Groen, founder and executive director of Centro de Cultura Arte Trabajo y Educación in Norristown, became a chairman of Montgomery County’s Democratic party 26 years ago, Republicans were the overwhelming majority.

“We were in the majority in one borough, Jenkintown,” said Groen, “We had nothing, basically.”

Since then, Montgomery County has become Pennsylvania’s strongest example of a trend that has been happening all over the nation: suburbs – where once Republican bastions – turn blue.

One of the factors is increased diversity. Montgomery County has seen steady gains among its Black, Latino, and Asian populations over the last several decades.

However, the county still remains 75 percent white, meaning that while diversity contributed, it is definitely not the only reason.

The changes within the parties have also played a role, as has the anti-Trump sentiment over the past four years, among many other things.

Read more about the political shift at the WHYY by clicking here.