Jacque Patterson is annoyed that he had to ask for campaign donations at a time when people were trying to buy their children’s Christmas gifts. Max Skolnik is antsy because he has not been able to knock on as many doors as he wanted because it was dark before many voters got home from work.

And Peter Shapiro finds himself explaining to supporters that he’s not needlessly littering front yards with campaign signs for an election they assume — incorrectly — is seven months away.

“One of the biggest questions I get when I am knocking on doors is, ‘There is an April 3 primary?’ ” said Shapiro, an at-large candidate for the D.C. Council.

For decades, the District has held primaries for mayor, council and Congress in September. But in one of the biggest changes to local campaigning since home rule, the city’s Democratic and Republican primaries will be held April 3 to make sure the District complies with new federal requirements that absentee ballots be mailed overseas at least 45 days before the general election to give soldiers and expats time to mail them back.

For candidates, operatives and voters, the shift is upending the political culture of a city that for decades conducted campaigns as flowers withered in summer heat, not before many had even bloomed.

With many voters unaware primaries are weeks away, candidates are struggling to raise money and identify supporters for a race that is often tantamount to a general election, since three out of four city voters are Democrats.

Candidates and observers say the District’s new election cycle strengthens the hand of incumbents, despite a federal investigation of the 2010 campaign of Mayor Vincent C. Gray (D) and an inquiry that led to the resignation of D.C. Council member Harry Thomas Jr. (D-Ward 5).

“It’s definitely a detriment to the challengers,” said Skolnik, a Democrat who is challenging council member Muriel Bowser (D-Ward 4). “I’m not making excuses, but it’s definitely a tougher calendar. . . . It’s way too early. . . . When we go around campaigning, people are like, ‘Why are you campaigning?’ ”

With many council seats up for reelection, there are contested primaries for the Democratic nomination in Wards 4, 7 and 8. Council member Vincent B. Orange (D) faces a primary challenger for an at-large seat. And there is a contested Republican primary for the Ward 7 council seat. (Council member Jack Evans [D-Ward 2] and Del. Eleanor Holmes Norton [D] are unopposed in their primaries.)

When the primaries were held in September, candidates didn’t have to file to run for office until early June.

They then had about six weeks to gather thousands of signatures to qualify for the ballot — an easier task in warm weather when residents gather on­ porches or in parks. Once they qualified for the ballot, candidates would campaign late into the evening at August festivals, the first day of school and Labor Day.

But the new primary schedule required that candidates pick up nominating petitions in mid-November. They had until Jan. 4 to turn them in.

With voters often traveling or shopping in the suburbs over the holidays, it was the worst time of the year to collect thousands of signatures, candidates said. For those who tried, it was smart to bring a couple of pens, said Tom Brown, a Ward 7 Democratic candidate.

“I remember being at the [Department of Motor Vehicles], and in the middle of people signing, my fingers almost froze and the pen froze,” said Brown, who heads a local job-training nonprofit group, Training Grounds. “While this winter was a little milder, are we going to have to look forward to campaigning in winters in the years to come?”

Candidates seeking media attention also have had to compete against news generated by the D.C. Council, which would have been on summer recess during the weeks leading up to the old September primary date. When Ward 3 Democrats held a forum for at-large council candidates last month, about 50 percent fewer people showed up than in previous years.

Candidates remain optimistic interest will perk up in the next few weeks, but some believe the new primary date has crushed their fundraising. Fewer donors are willing to give over the holidays or when they are filling out their tax returns, they say.

“In this time period, even the corporations are having Christmas parties, and they are like, ‘Oh, we will write that check a little later,’ ” said Patterson, who is running against council member Marion Barry (D-Ward 8) and three other candidates.

Former council member Sekou Biddle has raised $48,000, less than half of what Clark Ray had raised by this time in the cycle two years ago when he unsuccessfully challenged council member Phil Mendelson (D-At Large).

“It’s upsetting people’s rhythms,” Biddle said as he canvassed for support in the Lamond-Riggs neighborhood of Northeast last week. “It’s almost like people are not ready for there to be an election.”

Yet, as Biddle moved from door to door in a neighborhood dominated by seniors, there were signs that perhaps the new election date was starting to register, at least with the most reliable District voters.

“I read about it in the papers and have just been waiting for them to come around,” Alice Shaw, 77, said after Biddle persuaded her to put his campaign sign in her yard. “Anytime is good for me, because I’m retired.”

But Chuck Burger, a local Democratic consultant, predicted the change will make campaigning less effective than in previous years.

“The people who succeed are going to be the ones with deep pockets who can send out three or four mailings before the election,” Burger said.

Council member Mary M. Cheh (D-Ward 3), who helped negotiate the new primary date, agrees that April is “way too soon” and gives an advantage to the incumbents.

Cheh said the District could hold its primary as late as August and still comply with the Military and Overseas Voter Empowerment Act, although she said the council didn’t want to hold the primary when some voters would be on summer vacation.

Democratic strategist Tom Lidenfeld said District voters and candidates will get used to the earlier primary. He noted that primaries in many other cities, including Pittsburgh and Chicago, have been held in late winter or spring for years.

But Lindenfeld, who worked on the two mayoral campaigns of former mayor Adrian M. Fenty (D), said candidates will be starting their campaigns even earlier. The 2014 mayor’s race, for example, should begin by this fall, he said.

“Adrian Fenty started running two years before the election when he first ran [in 2006], and that was a September primary,” Lindenfeld said.