FOUR YEARS ago, polls showed that most Washingtonians were satisfied with the direction of their city but not so happy with the man who was leading it. Adrian M. Fenty, then mayor, was perceived as haughty and uncaring, more interested in his next biathlon than in sitting through one more community meeting. Some thought he was leaving parts of the city, particularly east of the Anacostia, behind others. Voters decided that his challenger could be counted on to continue the District’s progress with more inclusive programs and a defter touch.

The beneficiary of that decision, Mayor Vincent C. Gray (D), now faces a similar quandary. Mr. Gray, for the most part, opted to continue the Fenty program of school reform, economic development and professionalizing government, and voters once again think the city is doing pretty well. But once again they have reservations about the incumbent — in far larger numbers, in fact, than they doubted Mr. Fenty (D).

This time the problem is not so much arrogance as dishonesty and/or incompetence — a belief that Mr. Gray either knew or should have known about the corruption that pervaded his first mayoral campaign. If the polls are right, nearly three-quarters of likely Democratic voters in Tuesday’s primary want a change. An increasing number of them are confident (as are we) that this year’s large field of challengers offers one attractive alternative, a candidate who can keep the city on the right track while maintaining a higher ethical standard: seven-year D.C. Council member Muriel Bowser.

Some voters think it’s not fair to judge Mr. Gray based on allegations that have yet to be tested in court. He has denied all wrongdoing and has not been charged with any crimes, though his lawyer says he will not be surprised by an indictment. The only associate of the mayor who is openly claiming that Mr. Gray knew of the $668,800 illegal “shadow campaign” that helped elect him is Jeffrey Thompson, an admitted felon who got a sweet deal for his cooperation with authorities.

We understand the unease, but two aspects of the story are worth bearing in mind. First, one reason the federal investigation of the 2010 Gray campaign has dragged on so long has to do with Mr. Gray and his associates. The mayor declined to be interviewed by the U.S. attorney. His campaign assistant treasurer who handled day-to-day finances, Thomas Gore, admitted in court that he shredded documents that could have aided the investigation. Mr. Gray’s administration balked at requests for other documents sought by federal prosecutors.

Second, the facts as they are already known are sufficient to disqualify Mr. Gray for a second term. There’s no need to recite the sordid record in detail: the close associates from the campaign and D.C. Council who have pleaded guilty to felonies; the fringe candidate who was given a $110,000-a-year city job after leading attacks against Mr. Gray’s opponent in debates; Mr. Gray’s willingness to refer to his most generous donor as “Uncle Earl” to help keep the generosity — from a major city contractor — secret; that donor’s admission that he gave thousands of dollars to a close relative and to an intimate friend of the mayor.

With such a record, it takes a certain audacity — even recklessness — to ask voters for a vote of confidence. Fortunately, Ms. Bowser offers Washingtonians more than just a vote against Mr. Gray; she represents a positive new way forward.

Well-schooled in government, including a stint in Montgomery County and two solid terms on the D.C. Council, Ms. Bowser has an appreciation for the city’s successes that fuels her impatience to fix its failings. Accelerating school improvement, continuing economic development without pushing out the poor and middle class, investing in infrastructure and reforming government procurement are the issues that top her agenda and for which she has presented thoughtful ideas. After thinking long and hard about the ups and downs of Mr. Fenty, her self-described friend and supporter, she understands the critical importance of having a team that will speak out when necessary to tell her, “Muriel, stop. Muriel, listen. Muriel, go there.”

Her appeal extends to all demographics, in all parts of the city. That is a credit to the power of her vision and the strength of the campaign she has organized and run. Those are promising harbingers of how she would lead the city.