Santos began his sentence last month after pleading guilty to charges of money laundering and wire fraud, among other things, as part of a plea deal in April.

Santos was convicted of 23 felony counts, prompting widespread scrutiny over the handling and consequences of political corruption cases.

Ms. Greene, the hard-right House Republican from Georgia, called her former colleague’s seven-year sentence “excessive” in a letter to the U.S. pardon attorney.