D.C. Council member and mayoral candidate Muriel Bowser greets some of the first to arrive for early voting on Monday, March 17. The start to voting for the April 1 primary was delayed an hour and a half after more than 7 inches of snow fell in the District. (Aaron C. Davis/The Washington Post)

The same kind of wintry weather that has muted campaigning in the District’s first April mayoral primary returned Monday and depressed turnout on the first day of early voting.

Plans to open the city’s central polling place at 8:30 a.m. were pushed back to 10 a.m., and near closing time, elections officials recorded 158 ballots cast.

The D.C. Board of Elections went ahead with the start of early voting even as city offices, the federal government and courts closed, leaving streets around the Judiciary Square polling location all but deserted.

The board’s new online tool to help residents decide when to travel to polling places consistently showed a wait time of “0 minutes.” In 2012, the first year the District held an April primary for any local elections, an average of 500 residents cast ballots each day.

The trickle that did arrive Monday included mostly campaign workers for D.C. Council member Muriel Bowser and a couple of members of Mayor Vincent C. Gray’s staff. The low number provided little insight into voter interest in the first April 1 mayoral primary — and whether an embattled Gray would win his party’s nomination for a second term.

Voting began just seven days after federal prosecutors said that Gray (D) knew of a long-denied “shadow campaign” waged on his behalf to win the city’s top elective office in 2010. They also said for the first time that Gray had personally solicited more than $400,000 for the off-the-books effort, for which five of Gray’s associates have now pleaded guilty.

Gray has called the latest allegations “lies,” and his campaign did not mount an offensive Monday as early voting began.

The only candidate who appeared Monday morning was Bowser (D-Ward 4).

With an entourage of about 20 supporters, she greeted poll workers, then stood near a sign marking the closest spot to the polling entrance where candidates can campaign. Bowser posed for pictures with staffers and lunged to shake hands with the few people who arrived to vote who were unaligned with her campaign.

Bowser said she had planned to have her parents and other friends and family members vote Monday but delayed that until Tuesday because of the seven inches of overnight snow. Other campaigns had also discussed busing in supporters in recent days, but those plans were also put on hold.

The first person to vote Monday was Pete Ross, the Foxhall village resident who is again seeking to become the District’s “shadow senator,” to advocate for D.C. statehood. Second in line was a Gray staff member. The third was a campaign volunteer for Bowser. Most of the next dozen were also supporters of Bowser. Three said they were unaffiliated with her campaign.

One was Khadijah Tribble, 42, who said that of all the candidates, Bowser would give her four children the best chance to build careers and be able to afford to stay in the District as adults.

“They are all under 30 and in different phases of” independence, she said. Of Bowser, she said, “I think of all the candidates, she can inspire them to be the best citizens.”

The first voter who said he didn’t cast a ballot for Bowser or Gray was Dan Grant, a Georgetown University law student who said he cast his ballot for D.C. Council member Tommy Wells.

Grant, a D.C. resident since 2009, said the city seemed to have a poor record of picking the best candidate. “We need someone new,” he said.

In other campaign developments Monday, Wells (D-Ward 6) picked up a coveted endorsement from the city’s firefighters union.

Local 36 of the International Association of Fire Fighters endorsed Wells, calling him “the candidate that best understands the day-to-day public safety needs of our city.” Last week, the Fraternal Order of Police unit representing D.C. police officers, detectives and sergeants announced its backing of Wells, saying he “has not shied away from tackling systemic problems with the District’s public safety agencies.”

Besides being a boost for Wells, the nods come as a setback for fellow council member and mayoral candidate Jack Evans (D-Ward 2), who has run on a platform heavy on public safety and has enjoyed both unions’ support in his previous council elections.

On Monday, Gray announced the support of a seventh labor union — the Teamsters.

In a statement, Tommy Ratliff, president of Teamsters Local 639, said Gray is the “partner that we trust.”

“He has always been there for us, and we stand with him today,” Ratliff said.