Mayor Vincent C. Gray on Thursday will name the finance director of Phoenix to become the District’s next chief financial officer, ending a seven-month search to fill the powerful post.

Gray will introduce Jeffrey S. DeWitt at a noontime news conference at the John A. Wilson Building, according to two officials familiar with the mayor’s decision. The officials spoke on the condition of anonymity because they were not authorized to speak on the record.

DeWitt, 52, has served as the chief financial officer for Phoenix, the nation’s sixth-largest city, since 2009. According to an online résumé, he has worked for the Phoenix finance department since 1989 and oversees a $3.5 billion annual budget.

Should he be confirmed by the D.C. Council, DeWitt would replace Natwar M. Gandhi, who has held the office since 2000 and has been hailed for rehabilitating the city’s finances and helping repair its reputation on Wall Street and Capitol Hill.

This year, the District posted a $417 million budget surplus for the previous fiscal year, and some recent bond issues have received AAA ratings. But a series of controversies have battered Gandhi’s reputation in recent years, and he announced his retirement in late January, citing personal reasons, just months after securing a third five-year term.

In February, Gray appointed two city luminaries — former mayor Anthony A. Williams and former federal budget director Alice M. Rivlin — to lead the search for Gandhi’s replacement. Over the summer, the panel submitted at least four names to Gray, who interviewed the candidates in August, according to officials familiar with the process.

Last week, Gray said a selection was imminent, and top aides said the decision was pending a final background vetting. During a news conference, Gray said he was searching for “someone who has a proven track record of having managed these kinds of complex financial issues” — including working with bond rating agencies and overseeing a large staff.

While Gandhi had some experience with the District government before assuming the CFO post — he had helmed the city tax office before his promotion — DeWitt has no obvious ties to Gray or to the city. According to the online résumé, DeWitt is a former military police officer and has a master’s degree from Southern Illinois University.

A person who answered the phone at the Phoenix finance office Wednesday said DeWitt was on vacation. A message left for his assistant was not immediately returned.

Although the District is a much smaller city than Phoenix — 632,000 residents vs. 1.4 million — its government, encompassing city, county and state functions, is significantly larger. Phoenix’s annual spending of $3.5 billion is dwarfed by the District’s $12.1 billion overall budget.

DeWitt was named assistant finance director in 2002 and took over the department as acting director in 2009, as the city was beginning to grapple with a decimated property tax base from the housing market bust.

Six months after he was named to the post, Moody’s Investors Service lowered Phoenix’s bond rating outlook from “stable” to “negative,” citing another problem: a shrinking sales-tax base. The city, however, was able to refinance more $100 million in debt that year.

Under a Democratic administration in 2010, Phoenix faced a $300 million budget gap. DeWitt carried out plans to close the hole with program cuts, staff reductions and pay cuts of 3.2 percent for all union employees.

Some of the city’s biggest financial decisions have been made at the ballot box during DeWitt’s tenure. For example, voters recently approved a measure capping annual property tax increases at 5 percent.

As the city has worked its way out of the economic downturn, DeWitt has also aggressively pursued city tax cheats.

“We’re using data to find non-compliance,” he told the Arizona Republic. “You don’t need to audit everybody. You need to audit those people you know aren’t paying.”

Nikita Stewart contributed to this report.