Oregon Senator Jeff Merkley announced today that he is endorsing Bernie Sanders for the presidency. Sessions became the first U.S. Senator to endorse the Sanders’s run for the White House.

In an op-ed in The New York Times, Merkley struck a diplomatic tone in what has become an increasingly divisive fight between those supporting Hillary Clinton and those supporting Sanders.

“Hillary Clinton has a remarkable record. She would be a strong and capable president,” he said. “But Bernie Sanders is boldly and fiercely addressing the biggest challenges facing our country.”

Citing his youth spent growing up in a working class community in Oregon that provided his family with a comfortable standard of living, Merkley lamented the lack of similar opportunities for his children. Merkley is also one of the most progressive members in the Senate, having supported clean energy bills, campaign finance limits and increased taxations for corporations and the top 1 percent of earners.

“America has gone off track, and the outlook for the kids growing up there is a lot gloomier today than 40 years ago,” he said. “The problem is that our economy, both by accident and design, has become rigged to make a fortunate few very well off while leaving most Americans struggling to keep up.”

The endorsement cited many of the same talking points that have become a hallmark of the Sanders campaign, such as lack of upward economic mobility, working longer hours for less pay, and the concentration of new wealth in increasingly fewer hands. Merkley closed with an appeal to the political “revolution” Sanders claims will give his presidency the mandate to implement sweeping changes:

It has been noted that Bernie has an uphill battle ahead of him to win the Democratic nomination. But his leadership on these issues and his willingness to fearlessly stand up to the powers that be have galvanized a grass-roots movement. People know that we don’t just need better policies, we need a wholesale rethinking of how our economy and our politics work, and for whom they work.

The endorsement is likely to strengthen support for Sanders in Oregon, where 74 delegates are up for grabs in its May 17 Democratic primary. Sanders handily won Washington State, the only other primary on the West Coast so far, taking 73 percent of the vote to Clinton’s 27 percent.