As the nation heads into the 2020 Census, Oregon appears more likely than ever to gain a sixth congressional seat, according to new population estimates.

The Census Bureau estimates released Monday show that Oregon’s population growth – while slowing in the past year – remains strong enough to put the state in line for another seat.

“It looks like you’re safe [for another congressional seat] with about 100,000 people to spare,” said Kimball Brace, president of Election Data Services of Virginia. His firm uses several different models to project how congressional seats may be apportioned, and he said all of them show Oregon gaining a sixth seat.

That doesn’t mean it’s a sure thing. A big natural disaster – like the 2005 hurricane that devastated New Orleans – can quickly change a state’s population. And controversy over the Trump administration’s crackdown on illegal immigration may lead many people in immigrant communities to avoid participating in next year’s Census. Brace said California is on the verge of losing a congressional seat for the first time in that state’s history, particularly if immigrants are undercounted there.

The new estimates show that Oregon grew by 0.9% between July 2018 and July 2019, to a total of 4,217,737. Oregon came close to gaining a sixth congressional seat in 2010, and the state’s growth since then has far outpaced the nation.

Adding another congressional seat would give Oregon more clout in the U.S. House and make it marginally more important in presidential races – having a total of eight electoral votes instead of seven.

Democrats now control four out of the state’s five congressional seats. The only Republican is retiring Rep. Greg Walden, whose district includes all of eastern Oregon.

Behind the scenes, Democratic operatives have been talking about how to rejigger the district lines to their advantage. The legislature and the governorship are both in Democratic hands, and they will be in charge of drawing new lines if they maintain control after the next election.

“It’s the most political thing you’ll do” in the Legislature, said former state Sen. Chris Telfer of Bend, who was one of the chief negotiators of the 2010 redistricting plan. She served as a Republican but later shifted to the Independent Party of Oregon. “Whatever the Republicans do, the Democrats don’t like and whatever the Democrats do, the Republicans don’t like.”

Telfer said she hopes any new district will be drawn so that it can produce a competitive race.

While Democrats may have the upper hand in redistricting, some of them acknowledge it might be hard to create another Democratic-leaning seat without endangering their current incumbents. Instead they may focus on shoring up the seats they currently hold.

If a sixth district is added, each of the existing seats will have to be dramatically reduced in size. Currently, they run from about 800,000 residents in Walden’s district to more than 900,000 in the district of Democratic Rep. Blumenauer, who represents most of Portland. A sixth district would reduce each one to about 700,000 residents.

The prospect of a new congressional seat has also attracted the interest of government watchdog groups that are gearing up an initiative campaign to persuade voters next year to adopt an independent redistricting commission.

“It makes the proposal we want to put on the ballot even more urgent because all of the congressional districts will have to change,” said Norman Turrill, an Oregon League of Women Voters official who is a chief sponsor of the initiative campaign.

Since Oregon last gained a new seat in 1982, there have not been huge changes to any of the districts.

Copyright 2019 Oregon Public Broadcasting