But businesses would almost certainly spend to defeat the measure.

Earlier this year, Gov. Jerry Brown, a Democrat, signed legislation to increase the minimum wage to $10 an hour in 2016. The California Chamber of Commerce labeled the bill a “job killer” and said that such a large increase would raise the unemployment rate and put the state’s precarious economic recovery at risk. A spokeswoman for the group declined to comment on Mr. Unz’s proposal on Monday.

Mr. Unz brushes aside such criticism, saying the size of California’s economy — which, at roughly $1.9 trillion, is bigger than most countries’ — would prevent any large-scale movement of jobs to other states. Instead, he argues, it presents the best test case for the kind of national minimum wage increase he has advocated for years.

National polls suggest raising the minimum wage is popular, and Mr. Unz said he believed such a measure would pass easily in California, where an estimated 1.6 million residents earn less than $10 an hour. But it could cost millions to gather the nearly 750,000 signatures needed to get it on the ballot.

Mr. Unz entered politics in 1994 as a challenger to Gov. Pete Wilson for the Republican nomination, at one point accusing Mr. Wilson of being a closet Democrat. After his ballot measure against bilingual education passed in 1998 — he argued that such education kept students from learning English effectively and forced children to stay with other speakers of their native language — Mr. Unz backed similar successful measures in Arizona and Massachusetts. He became publisher of The American Conservative in 2007, writing opinion articles on the minimum wage, immigration and urban crime.

He left that post this year amid what he said were “ideological and administrative” differences. Officials at the magazine declined to comment.

Mr. Unz wrote in the magazine last year that manufacturing “sweatshops” that rely on immigrant workers, including those in the country illegally, were among the few industries that would be devastated by a higher minimum wage. “There’s a legitimate argument to be made that those kinds of businesses have no place in our economy,” he said, “and getting rid of them would eliminate the low-rung jobs that bring in new poor immigrants.”