Under the legislation, every adult citizen in Oregon who has interacted with the Department of Motor Vehicles since 2013 but hasn't registered to vote will receive a ballot in the mail at least 20 days before the next statewide election. The measure is expected to add about 300,000 new voters to the rolls...
...Oregon already has one of the highest voter registration rates in the nation -- 73 percent of Oregonians were registered to vote and 70 percent of them cast ballots during the 2014 general election.
Tony Green, spokesman for the secretary of state, said the legislation is expected to eventually capture all unregistered voters who are in the DMV database after taking actions such as obtaining or renewing a driver's license.
People eligible to vote will get a postcard saying they've been registered and have three weeks to opt out. They'll be automatically registered as unaffiliated but can select a political party from the postcard and return it to election officials through the mail.
Unfortunately, the only article I could find with a quick Google search was from Fox News so I won't link it, but the excerpt is above.
Combined with our vote by mail system, I hope and expect that turnout should be expanded. Perhaps the rest of the nation can watch our little experiment and see how it goes.