Oregon’s super-charged growth, with new residents arriving at a rate not seen since the 1990s, could boost its chances to add a congressional seat in 2020.

The Census Bureau said Tuesday that Oregon had grown by 1.71 percent in the past year, making it the sixth-fastest-growing state by percentage. Its 69,000 new residents also make it the ninth-fastest-growing state in absolute numbers.

A report from Virginia-based Election Data Services Inc. says Oregon is on track for another congressional seat, joining Florida, North Carolina and Texas.

Going from five to six seats in the U.S. House of Representatives, along with Oregon's two seats in the U.S. Senate, would also give the Democratic-leaning state slightly more weight in presidential contests.

Oregon would move from seven electoral votes to eight, although experts say that gain would likely be offset by growth in Republican states.

But Oregonians have been here before. In the late 2000s, Oregon was also a shoo-in for a sixth House seat -- until the Great Recession hit, putting a damper on migration.

"We're probably as likely to get a new seat as not at this point," said Jim Moore, director of the Tom McCall Center for Policy Innovation at Pacific University.

Seats in Congress are shuffled between states every 10 years based on results from the Census. Oregon last gained a seat after the 1980 Census, and it's long been on the cusp of another.

But a lot can happen in the four years leading to the next Census.

"The change in administration could have a profound impact on population change and growth in this nation," said Kimball Brace, the president of Election Data Services. "Having worked with Census data and estimates since the 1970s, it is important to remember that major events like Katrina and the 2008 recession each changed population growth patterns, and that impacted and changed the next apportionment."

Another economic downturn could dramatically slow migration again. About 85 percent of the state's population growth came from migration last year, and migration tends to follow the health of the economy. Oregon's job market has been growing faster than nation overall.

And even if the economy doesn't falter, forecasters who predicted a spike in population growth this year expect it taper in the near future. The state's short-term population forecasts call for slower growth each year from 2017 to 2020.

Metro's population forecasts for the Portland area also call for slightly slower growth.

If Oregon does gain a congressional district, it would further concentrate political influence in the Portland area, Moore said.

The state Legislature would be tasked with redrawing congressional maps, with the result included in a bill for the governor to sign or veto.

Regardless of the politics, the state's mostly rural 2nd congressional district among the largest in the nation by size, would likely grow even larger and more dispersed. The Portland metro area would probably be further divided among several districts.

"It's a further marginalization within the state of the rural voters," Moore said. "But that's what the population has been showing us. The only places that are losing population or staying even are the rural areas."

It would also likely have little impact on the national political stage.

A new blue district in Oregon would be offset by new red districts elsewhere. Election Data Services found that its projections would not have changed the outcome of any Electoral College decisions in any of the past five presidential contests.

-- Elliot Njus

enjus@oregonian.com 503-294-5034 @enjus