President Donald Trump, meanwhile, appears to have changed his tune. After saying Congress should “eliminate Daylight Saving Time” in December 2024, he called for the opposite move earlier this month, a day after a Senate hearing on the issue chaired by Sen. Ted Cruz (R-Texas).

“The House and Senate should push hard for more Daylight at the end of a day,” Trump wrote on Truth Social. “Very popular and, most importantly, no more changing of the clocks, a big inconvenience and, for our government, A VERY COSTLY EVENT!!!”

Daylight saving time, which typically starts on the second Sunday in March and ends the first Sunday in November, involves setting clocks forward by one hour—resulting in more evening daylight during the warmer months of the year. Standard time, in effect during the other four months, aligns with solar time, meaning noon on the clock coincides with the sun hitting its highest point in the sky. 

Trump’s reversal was a disappointing development for Jay Pea, the founder and president of Save Standard Time, a volunteer-run nonprofit that works with sleep medicine groups to lobby in Congress and state legislatures.

“We need to try to get him to see that golf will still happen with standard time,” Pea said in an interview with Fortune. “And if we want to make Americans healthy again, we need standard time.”

Pea said his organization’s messaging has picked up steam among supporters of Health and Human Services Secretary Robert F. Kennedy Jr., who has promised to “Make America Healthy Again.”

“We just haven’t gotten through yet to the people at the top of the MAHA [movement],” Pea said. “I’m hopeful to turn their heads soon.”

Pea and other standard time advocates say it’s better for peoples’ circadian rhythms, or “biological clocks,” and, therefore, public health and safety, as well as productivity.  

A recent Gallup poll suggests most Americans are on board, with 54% of U.S. adults saying they are ready to get rid of daylight saving time, compared to 40% who remain in favor of the practice. In a question asked of different participants, 48% of Americans said they preferred having standard time the whole year. Meanwhile, just 24% and 19% of those polled said they wanted permanent daylight saving time or a preservation of the status quo, respectively.

Nonetheless, efforts in Congress to stop the changing of clocks have so far exclusively called for a switch to daylight saving time, based, in part, on the premise Americans would prefer an extra hour in the evening to spend time outdoors, shop, or otherwise enjoy the sunshine.

A Congressional push for daylight saving time

Led by current Secretary of State Marco Rubio, a bipartisan group of senators introduced the “Sunshine Protection Act” in 2021. The bill was passed by unanimous consent, which is typically used to expedite routine and uncontroversial procedural moves, but it stalled in the House. An updated version sponsored by Sen. Rick Scott (R-Fla.) was put forward in January.

Eighteen states have passed legislation to institute daylight saving time permanently if Congress acts, according to the National Conference of State Legislatures, but many of those same constituencies are also currently considering bills that favor standard time instead. Under current law, states only have the option to opt out of daylight saving time, which both Arizona and Hawaii did in the late 1960s.

“When I talk to Congress members, there are many who tell me that they’re just sponsoring the Sunshine Act because it’s the only bill they see,” Pea said. “If someone else would file a bill for standard time, they would sponsor it also.”

Besides legislative inertia, Pea said, another political challenge is the association daylight saving time enjoys with summer.

“But you cannot magically turn winter into summer,” he said. “By changing your clock, you would only make winter more miserable, because it would be dark until 8:30 or 9 [a.m] in many states.”

The U.S. briefly experimented with permanent daylight saving time in 1974, with President Richard Nixon signing a bill aimed at conserving energy usage amid the oil crisis. During the winter, however, Americans soured on getting to work or school in the dark, particularly when incidents of schoolchildren being struck and killed by vehicles became national news. By October 1974, President Gerald Ford had signed a bill to put the U.S. back on standard time for four months of the year.

The offices of Scott and Sen. Patty Murray (D-Wash.), also a champion of the Sunshine Protection Act, did not immediately respond to Fortune’s requests for comment. The same went for the office of Cruz, who is yet to officially express his preference.

Arguments for daylight saving time year-round, however, tend to emphasize the relationship between sunshine and leisure spending. Jay Karen, the CEO of the National Golf Course Owners Association, told the Senate committee eliminating daylight saving time would cost facilities an estimated $1.6 billion in green fees, or $162,000 per course. Making it permanent, meanwhile, would represent a $1 billion tailwind for the industry, he said.

Rubio and Murray argued in a 2021 op-ed that economic activity fell during standard time. They referenced a study from the JPMorgan Chase Institute, which found daily card spending decreased 3.5% in Los Angeles compared to Phoenix, where clocks are not changed, in the month following the end of daylight saving time.

Researchers had framed their findings differently from Rubio and Murray, however, pointing to a paltry spending jump when clocks sprang forward in the spring.

“Our unprecedented view of spending around the beginning and end of [daylight saving time] does not support consumer spending claims of DST advocates,” they wrote in 2016.

Still, the current debate in Congress and state legislatures may just be getting started.