Representative Duncan Hunter of California is expected to plead guilty to allegations that he misused campaign funds, according to a federal court docket published on Monday and an interview he gave to a San Diego television station.

Mr. Hunter is accused of spending more than $200,000 on personal expenses. An indictment detailed spending on lavish family vacations to Hawaii and foreign countries, large bar tabs, and grocery purchases for his family.

Before the indictment was released last year, Mr. Hunter, a veteran of the wars in Iraq and Afghanistan, boasted a sterling political résumé and a picture-perfect family. But the evidence gathered by prosecutors revealed his family’s deep financial trouble and a fraught home life.

In Washington, he developed a reputation for heavy drinking. At his family’s suburban home in California, the indictment showed, the spending was quotidian: thousands of dollars in campaign funds spent at Costco, at Walmart, or on fast-food runs.