The historic Democratic wins in the 2018 election are no fluke — but rather a sign of Colorado’s political future.



A new analysis by The Colorado Sun found that all but one of the state’s seven congressional districts is shifting to favor Democrats, including once rock-solid Republican turf. And a handful of one-time swing counties now appear solidly Democratic in the era of President Donald Trump.



The findings provide more evidence to suggest Colorado is turning blue amid political and demographic shifts, and they offer a forecast for what to expect in 2020 and beyond.



The intensity of the blue wins in Colorado increased from 2014 to 2018 in the three districts controlled by Democrats, the analysis found. And in three districts held by Republicans, the margin of victory shrunk over the same time period. In the 6th Congressional District, this led to the upset of five-term Republican U.S. Rep. Mike Coffman by Democrat Jason Crow.



The outlier is the 5th District based in Colorado Springs. But even Republican incumbent Doug Lamborn saw his huge 2016 margin of victory reduced to traditional levels in 2018, the analysis found.



A breakdown of the results shows that only seven of the state’s 64 counties split their vote in the top-of-the-ticket races in the 2014, 2016 and 2018 elections. This year, Democrat Jared Polis’ win in the governor’s race even flipped two traditionally Republican counties, Garfield and Chaffee.



The tally of votes in the past three statewide elections — whether for U.S. Senate, governor or president — suggests that only these seven counties are toss-ups in the future. All but Larimer and Pueblo are small in terms of population, too.



A deeper analysis indicates that five traditional swing counties on the Front Range — Arapahoe, Adams, Broomfield, Jefferson and Larimer — are only becoming more blue with Trump as the head of the Republican Party. The population increases in these counties is another possible factor, as U.S. Census Bureau estimates show between 2014 and 2017 more than 90,000 people moved to the area.



From 2014 to 2018, the Democratic margin of victory grew significantly in each county. Among those, only Larimer went for a Republican — back in 2014 with the upset victory by Cory Gardner in the U.S. Senate race against Democratic incumbent Mark Udall.



At the state level, the size of Democratic wins in Colorado increased in each of the past two elections, the Sun analysis found. The average Democratic margin in the past five statewide races at the top of the ticket is 3.9 percent.



The numbers highlight the tough odds facing Gardner’s re-election bid in 2020, and the struggle Republicans will face in retaking the ground lost to Democrats in the 2018 election.

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