MONTGOMERY, Alabama — To Democrats, Senate candidate Doug Jones’ stunning victory in reliably Republican Alabama is more than a quirky one-off. Instead, party leaders cast the upset as a sign of growing nationwide momentum among voters opposed to President Trump and an indication that Democrats shouldn’t shy away from competing in Republican territory.

Democrats were bolstered in particular by the higher turnout in Alabama among African-Americans, particularly women, young voters and residents of urban areas, along with a diminished Republican advantage in some small towns and rural areas. The Alabama returns track other high-profile elections where Democrats have pulled out victories this year, including the governor’s seat and other statewide offices in Virginia, and several dozen state legislative seats around the country.

“We’re feeling the sunshine from Alabama all the way in Washington state,” said Gov. Jay Inslee, who chairs the party’s gubernatorial campaign arm. “We’re seeing a passion for voting (and) this phenomenon exists in every state. It will expand the universe of competitive races.”

The Senate and House lineup for 2018 still poses real obstacles for Democrats as they seek a path back to the majority. But party officials also see opportunities on the horizon to flip enough seats to reclaim control of Congress, dent Republican advantages in statehouses and diminish Trump’s political sway in the final two years of his term.

“Obviously the path to a majority got a little wider, but it is still a long and winding road,” said Maryland Sen. Chris Van Hollen, who runs Senate Democrats’ campaign efforts.