In the D.C. at-large race, a cloud of mismanagement surrounding Michael A. Brown proved his downfall. (Tracy A. Woodward/The Washington Post)

In June, Michael A. Brown addressed his latest small-bore financial difficulty — the most recent of several federal tax liens filed against his Chevy Chase home.

“Old news,” the at-large D.C. Council member called it, speaking to reporters before a council meeting. “There is nothing new. Voters have vetted me on all those issues.”

Indeed, Brown (I) was elected in 2008 with some of his past issues as public knowledge: a 1997 guilty plea to a federal campaign-finance misdemeanor, unpaid bills for a Verizon Center luxury box.

At the time, voters did not care much about those problems. Nearly 72,000 of 265,000 voters cast ballots for Brown, enough that he found his way to elective office after unsuccessful runs for mayor and Ward 4 council member.

But on Tuesday, voters gave Brown, the dapper and charming son of the late commerce secretary Ron Brown, a more-thorough vetting.

Once considered a leading contender for mayor or council chairman, Brown was laid low by a longtime D.C. political aide with a laidback sensibility seemingly more suited for a game of Hacky Sack than big-city politics.

Winner David Grosso did get lucky.

That tax lien was not the last of Brown’s problems. Since his 2008 win, he has been buffeted by revelations of late payments on income and property taxes, a repeatedly suspended driver’s license and late rent payments, among other issues.

And, crucially, the cloud of mismanagement extended to Brown’s current campaign. In late June, he revealed that a “substantial” amount of money had gone missing from his campaign account — later revealed to be the bulk of his war chest — giving Grosso a sudden cash advantage.

Grosso became skilled and relentless at using the headlines to attack Brown’s trustworthiness in candidate forums, media interviews and direct mail. Brown could only flail back by highlighting Grosso’s 19-year-old marijuana arrest.

Perhaps without the campaign theft, things might have turned out differently for Brown. Perhaps he might have fended off all those other questions — particularly if he had that missing $113,000 in his campaign coffers to spend.

But the questions fueled by the missing money made the cloud too thick. More than four months after Brown pointed to his former campaign treasurer as the alleged thief, no arrest has been made in the case. He said federal prosecutors had cleared him of wrongdoing, but the U.S. attorney’s office would not corroborate the claim.

By the numbers, Brown’s support collapsed sharply, and not just in the western wards where Grosso swamped him. Brown won fewer votes than he did in 2008 in every city ward, including the eastern wards where he outpolled Grosso. As it stands, Brown won 20,000 fewer votes Tuesday than in 2008. His biggest drop (4,400 votes) was in his home ward, 4.

This story is not over, however. This spring, D.C. voters will pick an at-large member to replace Phil Mendelson (D), who easily won his bid to continue for two more years as council chairman.

Brown, despite the advantage of running in two presidential cycles with Barack Obama on the ballot, has spent the past five years as a nominal independent in order to claim one of the non-Democratic at-large seats enshrined in the District charter. That’s been an uncomfortable position for Brown, the son of a beloved Democratic national chairman, erstwhile Obama surrogate and self-proclaimed “independent Democrat.”

Should he choose to salvage his political career by pursing the vacated at-large seat, he could find himself back on the council in a more natural pose — as a bona fide Democrat.

But that comes with a risk: Losing a special election race on the heels of his general election loss could put a boldface exclamation point at the end of his political obituary.