As tensions build over a San Francisco ballot measure that would tax businesses to fund homelessness initiatives, the debate over how to support a population with little political power has escalated into a war between people with the most. Funding the opposition to Proposition C are some of the city's most prominent tech titans, according to campaign filings released Thursday. But outspending them all is one man and his company that, together, have contributed more than $5 million, as part of a vocal campaign that businesses must help end the city's homelessness crisis. The man is Marc Benioff, and the company is Salesforce—the city's largest private employer, the owner of the tallest building in the city, and the sponsor behind a new ( now-crumbling ) transit center. Benioff, Salesforce's chief executive officer, has emerged as Prop C's most ardent supporter—pitting himself against Jack Dorsey, the chief executive officer of Twitter and Square, who opposes the measure along with Mayor London Breed.