The District’s nascent mayoral race sprang to life Wednesday night with the six Democrats vying to replace Mayor Vincent C. Gray jumping at their first chance to debate one another other in front of a live audience.

The candidates have not yet turned in the signatures needed to qualify for the April 1 primary, and the incumbent has not yet announced whether he will seek reelection. Still, the first face-to-face encounter among the other mayoral hopefuls, sponsored by the D.C. Bar Association, offered a few lessons about the early shape of the race:

●If Gray (D) decides to run, he’ll do so with a target on his back. The candidates in this crowded field showed Wednesday night that they are willing to climb over one another in order to be viewed as the antidote to years of ethical scandals under Gray.

Candidates questioned the mayor’s integrity and harped on questions raised by the ongoing federal investigation of a secret “shadow campaign” by a city contractor to help elect Gray in 2010.

D.C. Council member Tommy Wells (D-Ward 6) opened the forum by saying that any extension of the city’s “corrupt government” would only stall its progress and promising that he would seek to “restore integrity” to city hall. Council member Muriel Bowser (D-Ward 4) echoed the theme, saying she was running because the District deserved a “fresh start.”

●With four current council members in the race — Wells, Bowser, Jack Evans (D-Ward 2) and Vincent B. Orange (D-At Large) — these candidates know one another intimately, including every embarrassing and questionable action taken in the council chambers at the John A. Wilson Building.

With candidates facing a compressed election calendar and an early April primary, Wednesday provided evidence that the four lawmakers are comfortable confronting one another and will seek to use insider knowledge to their advantage.

Evans and Orange, for example, found themselves on the defensive early on in the forum for voting against a censure of Marion Barry (D-Ward 8) this fall, after Barry reported taking money from a city contractor. Those two and Bowser also took heat from Wells for voting to delay a voter-approved election for attorney general.

The dynamic could prove revealing, so long as the candidates don’t delve too deeply into the minutiae of council politics while making their attacks.

● The race has two decided outsiders and political neophytes — Busboys and Poets owner Andy Shallal and former U.S. Chamber of Commerce vice president Reta Jo Lewis.

Shallal showed a readiness to mix it up in the debate, saying that he would consider flying the D.C. flag upside down in protest until the District is granted statehood, and that he wants to expand the electorate by letting 17-year-olds vote. Lewis struggled at times to articulate concise positions but also provided one of the debate’s most memorable moments, calling out Evans, Orange and Bowser for “trying to explain away” their efforts to upend the will of voters on the attorney general race. She also said the District risked “losing its soul” to development and gentrification.

Aside from ethics, the impact on the city of a tidal wave of economic development was a major theme among all six candidates. All said the District must do more to retain longtime residents and affordable housing, though few provided specific policy proposals.

Bowser said that, if elected, she would create position of deputy mayor for east of the Anacostia, to coordinate development and job creation in Wards 7 and 8.