Oregon Gov. Kate Brown smiles after signing an automatic voter registration bill, Monday, March 16, 2015, in Salem, Ore. (AP Photo/Don Ryan)

On Monday, Oregon became the first state that will automatically register voters using information collected at the DMV.

Anyone eligible will be given an opportunity to opt out — but otherwise they become registered voters. The administration estimates that about 300,000 people will be added to the rolls, increasing the number of registered voters from 2.2 million to 2.5 million.

Federal law already requires states to allow people to register to vote while filling out paperwork for a driver’s license. Oregon’s new law will make the process automatic.

“I challenge every other state in this nation to examine their policies and find ways to ensure that there are as few barriers as possible in the way of a citizen’s right to vote,” Oregon Gov. Kate Brown (D) said at the signing ceremony on Monday.

The law marks a victory for Brown, who introduced the measure in January when she was still secretary of state. The bill, HB 2177, passed without a single Republican vote.

Republicans argued that automatic registration amounts to coercing people to vote. “Government should nudge people to do the right thing but not force people,” Rep. Knute Buehler (R ) told The Bend Bulletin in January.

Brown proposed a similar bill in 2013, which passed the house but died after Democrat Betsy Johnson joined 14 other Republicans to kill it in a 15-15 senate vote. In 2014, Democrats won two additional senate seats, making the bill’s passage this year almost a foregone conclusion.

Oregon, the first state to conduct all its elections by mail, is already a pioneer at expanding voter access. The secretary of state’s estimates that about 800,000 people there are currently eligible to vote but unregistered.

As Reid Wilson wrote in February, the law will likely give a boost to Democratic groups, which already spend a significant amount of money on get-out-the-vote efforts:

Left unsaid at the Rules Committee hearing were the political ramifications of adding so many new voters in a state where only 2.2 million people are registered. Democratic-leaning outside groups spend millions across the country to register voters, primarily low-income and minority voters who are less likely to sign up through other means. Removing the need to register those voters would ease the strain on liberal groups’ budgets, allowing them to focus more on getting those new voters to return their ballots.

Others say that automatic registration will lift all boats. As Niraj Chokshi reported in March, the Brown administration also expects an influx of affiliated voters brought in by the new law:

Democrats generally view the removal of barriers to voting as advantageous, since minority and low-income citizens who often support their candidates tend to be less likely to register. But the bill is expected to swell the ranks of a separate group of voters more than any other, [spokesperson Tony] Green says.

It is likely that “there will be more voters affiliated with no party than voters affiliated with any of the major parties,” Green said. Just last month, the state’s independent party achieved major-party status after claiming 5 percent of registered voters.