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Vincent Gray spent his only term as Washington's mayor dogged by allegations of corruption. Then, three weeks before the 2014 Democratic primary -- the only local election that matters in what is essentially a one-party town -- a prosecutor said in court that Gray knew about an illegal slush fund that aided his 2010 campaign. 

Predictably, Gray lost his bid for re-election. But now, with Wednesday's announcement that federal prosecutors decided not to charge Gray with a crime after investigating his 2010 campaign, he appears poised to return to politics.   Gray, 73, is pondering a bid for the D.C. Council. He could run in his home ward east of the Anacostia River, where he still has a strong support base. Despite the allegations, voters in his home ward picked him over current Mayor Muriel Bowser by more than 2-to-1 last year. He could also test whether voters citywide feel he's been vindicated by trying for an at-large council seat. 

Six people who worked on Gray's 2010 campaign pleaded guilty to felonies as prosecutors tried to build their case during an investigation that spanned nearly five years. The most serious revelations involved a $660,000 slush fund that an influential businessman used to boost Gray's get-out-the-vote efforts. Gray has repeatedly apologized for his aides' actions, but he has maintained he never broke any laws and had no idea that anybody else was, either. 

The U.S. Attorney's office formally ended the investigation Wednesday, announcing that there wasn't enough evidence to charge anyone else. 

Historically, District of Columbia voters have forgiven much higher-profile transgressions. Marion Barry returned to the council less than a year after he was released from prison on a drug charge. Two years later, he was elected to a fourth term as mayor. 

"If Vince decides to run again, voters can once again judge him based on his record of service," said Chuck Thies, who managed Gray's 2014 campaign. "The innuendo and smear campaign led by federal prosecutors has been discredited." 

Democratic D.C. Council member Mary Cheh was a firsthand observer of Gray's rise and fall. She endorsed him over Adrian Fenty in 2010 despite Fenty's popularity in her wealthy, majority-white ward. Then she watched in horror as Gray's administration was derailed by revelations of lawless behavior by his campaign aides. 

Cheh called on Gray to resign, saying city voters deserved a "do-over." But now, she thinks he'd be a welcome addition to the council, the city's 13-member legislature where he served for six years before becoming mayor, including four years as chairman.

"He was an excellent chair of the council, an excellent member of the council," Cheh said, adding that aside from the questions about how he took office, "he was actually quite a good mayor. If he returns to office in some fashion or another, I think the District will benefit." 

As mayor, Gray, was a detail-oriented technocrat who earned praise for his management of city finances. The city enjoyed low crime, an increasing population and a booming real estate market during his tenure, and Gray maintained the key school reform measures launched under Fenty. 

However, the succession of Gray campaign aides who pleaded guilty, along with criminal convictions against three council members for unrelated crimes fueled perceptions that the local government was hopelessly corrupt even as the city thrived.

Bowser campaigned on the idea of a "fresh start" for the city, and Gray is a potential antagonist for her. He declined to endorse her after she defeated him in the primary, and the two are not on speaking terms. However, their differences are rooted more in personality than politics: Both are mainstream Democrats with liberal views on social issues and ties to the business community.

Bowser's supporters believe she would have defeated Gray even without the revelations from the U.S. Attorney's office, pointing to her 10-percentage-point margin of victory and her support across broad swaths of the city. 

Gray kept a relatively low profile after he left office on Jan. 1. He hasn't found a full-time job. His attorney, Robert Bennett, and others close to Gray said he had difficulty moving on with his life with the investigation looming over him. 

Gray issued a statement Wednesday that hinted at a return to politics. Through his attorney and Thies, he declined to comment further. 

"Here in the District and around the country many people have had their faith in our justice system tested," Gray said. "Justice delayed is justice denied, but I cannot change history. I look forward to getting on with the next chapter of my life, which will no doubt be dedicated to service."