Plenty of contentious issues loom ahead of Sunday’s elections in Japan: A shrinking economy, falling real wages and no trade deal to shield against U.S. President Donald Trump’s tariffs.

But the narrative has instead been dominated by a fringe group and its chatter about the nation’s growing cohort of foreign residents.

A spike in the polls for the right-wing Sanseito has alarmed mainstream parties and shifted the debate to its anti-immigration policies. Leader Sohei Kamiya denounces "globalism” and wants fewer overseas workers. The party’s "Japanese First” slogan intentionally riffs on Trump. It won three seats in last year’s Lower House vote and three more in Tokyo’s recent assembly election.