The Supreme Court returned Mr. McDonnell’s case to an appeals court for an assessment of whether prosecutors had presented evidence to satisfy the narrow definition of corruption announced Monday. If so, prosecutors may seek to retry Mr. McDonnell, but under the stricter standard.

In a statement, Mr. McDonnell said that he was innocent and that he expected to be vindicated.

“I have not, and would not, betray the sacred trust the people of Virginia bestowed upon me during 22 years in elected office,” Mr. McDonnell said. “It is my hope that this matter will soon be over and that my family and I can begin to rebuild our lives.”

An appeal by his wife, Maureen, who was also convicted in the case, was put on hold while the court heard his case. Her conviction is likely to be thrown out now.

Mr. McDonnell, a Republican who served from 2010 to 2014, was charged with using his office to help Jonnie R. Williams Sr., who had provided the McDonnells with luxury products, loans and vacations worth more than $175,000 when Mr. McDonnell was governor. The gifts themselves were legal, and the question in the case was whether they were part of a corrupt bargain in which Mr. McDonnell reciprocated by using his office to help Mr. Williams.

Mr. McDonnell arranged meetings for and attended events with his benefactor. But Mr. Williams, whose company made a diet supplement, did not have any real success in obtaining support from the state for his product. A jury found that Mr. McDonnell’s actions amounted to corruption, and a federal appeals court upheld the conviction.