Mr. Villines opposes that sales-tax increase or any other tax boost. His reasoning is that higher taxes will weaken the economy further, because people will have less money to spend on goods and other services. The problem, he says, is spending. As an example, he cites the states' public schools, which keep getting more money each year, even as enrollment is declining in K-12 grades. "There is not a revenue problem in California," he says. "There is a spending problem." Mr. Villines's views are crucial because he has emerged as perhaps the most influential Republican legislator. Unlike his counterpart in...