A federal investigation of the 2010 campaign has been ongoing for most of Gray's term. Four people who worked on the campaign have pleaded guilty to felonies, two of them for helping to arrange and spend $653,000 in illicit funds on Gray's behalf. Prosecutors called the effort a "shadow campaign" that tainted Gray's victory over then-Mayor Adrian Fenty.
Gray maintains he did nothing wrong, although he has declined to discuss the case in detail. His attorney, Robert Bennett, declined to say whether he gave the mayor any advice about running for re-election.
Gray arrived late Monday afternoon at the D.C. Board of Elections to pick up nominating petitions. He has one month to collect 2,000 signatures to get his name on the ballot.
Supporters maintain that after a rocky first few months in office, Gray has been a conscientious leader for a city that's enjoyed declining violent crime, soaring property values, a rising population and improving schools. The mayor contends he has fulfilled his promises to shore up the city's finances and make strides in education, public safety, economic development and environmental stewardship. He's also been a forceful advocate for greater autonomy for the city, whose laws and policies are subject to review by Congress.
Gray is a late entry into the race, with the Democratic primary scheduled for April 1. Some of his opponents have been running for the better part of a year. The mayor remained coy about his intentions for so long that many observers -- including some of his supporters and potential rivals -- assumed he had no intention of running.
As the incumbent mayor of a thriving city, Gray should have no trouble raising enough money to compete, but many of his influential 2010 backers have abandoned him, and he will have to rebuild a campaign organization from scratch. His approval ratings tanked amid revelations of the "shadow campaign" and a scandal involving minor candidate Sulaimon Brown, who was paid by Gray campaign workers to stay in the race and make negative comments about Fenty.
Brown was rewarded with a $110,000-a-year job in the Gray administration but was fired in early 2011 after less than a month in the position. He then came forward with his allegations, which led to the federal probe. Two people pleaded guilty to paying Brown with Gray campaign funds and trying to cover up the transactions.
A Washington Poll in July 2012 put Gray's approval rating at 29 percent and his disapproval rating at 59 percent.
Gray enters a crowded field of candidates from which no obvious front-runner has emerged. Four D.C. councilmembers -- Muriel Bowser, Jack Evans, Vincent Orange and Tommy Wells -- are seeking the city's highest office. Other Democratic candidates include former State Department official Reta Lewis and Iraqi-born restaurateur Andy Shallal.
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