DENVER (AP) – Republicans told a Denver District Court judge on Tuesday that Democrats are trying to undo electoral gains made by about 1.5 million voters over the past decade by moving them into new congressional districts.

Democrats countered that Colorado has changed since the state’s seven districts were drawn up a decade ago and that new districts are needed.

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Both parties made their opening arguments before Judge Robert S. Hyatt, who will draw a new map required every 10 years following the U.S. Census. Colorado’s Legislature failed to do so in its spring session.

Attorney Richard Westfall, representing state Republicans, argued that Democratic proposals would force 1.5 million voters into new districts.

“The lines you are being asked to move affect real people,” Westfall said. “Decades of representative interests are reflected in that map.”

GOP leaders say Democrats are trying to change districts held by GOP Reps. Mike Coffman in Denver’s southern suburbs, Cory Gardner in eastern Colorado and Scott Tipton in south and western Colorado. Coffman and Gardner’s districts lean heavily Republican, while Tipton’s has become competitive in recent years.

Attorney Mark Grueskin, representing Democrats who are offering their own maps, told Hyatt that many communities no longer share the same interests they shared a decade ago. Colorado’s forests and mountains need more help than one representative can provide, while oil and gas development has exploded up and down the Front Range, he said.

Grueskin said Republicans want no major changes because they hold a 4-3 advantage in Washington.

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In the early 2000s, Republicans held five of the seven seats. Democrats held five seats before the 2010 election.

“There is no way these districts can stay the same,” Grueskin said.

Court criteria for redistricting include keeping communities of interest together, preserving county and municipal boundaries and avoiding racial discrimination. The ideal size for a Colorado district is about 718,000 people.

Hyatt could adopt one of the suggested maps or order new maps to be drawn. The trial is expected to last two weeks.

Hyatt is hearing lawsuits filed by individuals and advocacy groups affiliated with both parties. Colorado Republican Party chairman Ryan call said both parties are working closely with the plaintiffs.

– By Steven K. Paulson, AP Writer

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