Daylight saving time officially ends at 2 a.m. local time on Sunday, Nov. 1, when most of the U.S. "falls back" an hour, CBS News and Yahoo report.

Americans have fallen back on the first Sunday of November since 2007, when a 2005 law moved the end date from the last Sunday of October. Most people gain an hour, making up for the hour lost when clocks "sprang forward" on March 8.

But the routine ritual is now wrapped in an unusual political fight: President Trump supports making daylight saving time permanent, and Yahoo and CBS report he went as far as posting what he said was fellow Republican Sen.

Tom Cotton's cellphone number, urging people to call the Arkansas senator to push the Sunshine Protection Act through the Senate.

The standout development inside this story, as Yahoo tells it, is Trump accusing Cotton — a member of his own party — of single-handedly holding up the legislation.

Yahoo reports that Trump even posted to social media what he said was Cotton's cellphone number and urged supporters to call the senator.

Cotton's response, per Yahoo, was a history lesson: Congress has tried permanent daylight saving time before, only to reverse course "once Americans experienced absurdly late sunrises in the winter."

It is a striking reversal of expectations — the twice-yearly clock change, long treated as a bipartisan nuisance, has become a public feud between a president and a senator from his own party, fought out over social media.

Yahoo and CBS News report that the Sunshine Protection Act cleared a major hurdle earlier this year, passing the House in July before heading to the Senate, with a provision letting states opt out of daylight saving time altogether before the law takes effect.

The bill remains stuck, and there is a ticking clock: per Yahoo and CBS, the legislation — like other bills awaiting action — is set to expire in early January when the new class of lawmakers elected in Tuesday's midterm elections takes office.

If it dies, Yahoo notes, the effort must start over in both chambers. Separately, NBC News reports Trump urged Senate Republicans on Truth Social in early October to "get moving" on the bill, claiming clock changes "cost our Country a fortune."

The U.S. first adopted daylight saving time in 1918 during World War I to conserve fuel, according to the Congressional Research Service as cited by CBS and Yahoo. Congress repealed it after the war, then re-enacted it from 1942 to 1945 during World War II.

NBC News adds that President Richard Nixon briefly moved the nation to year-round daylight saving time in 1974, but the extended morning darkness was widely panned and blamed for incidents of students being struck by vehicles, and Congress reversed it after Nixon resigned.

Uniform national dates didn't arrive until the Uniform Time Act of 1966. Both prior experiments with year-round daylight time were short-lived — the 1970s version, per CBS, ended before reaching the 10-month mark.

The stakes are more than cosmetic.

Some studies suggest permanent daylight saving time could reduce traffic accidents and crime, NBC News reports, but many health and sleep researchers oppose it, citing the hazards of dark mornings — more children walking or driving to school in the dark — and increased health risks when clocks are not aligned with the sun.

Per NBC, sleep experts actually prefer the current back-and-forth to permanent daylight saving time. Hawaii and most of Arizona already sit the whole fight out, staying on standard time year-round, as do several U.S. territories.

For now, the immediate change is practical: phones set to update automatically will shift overnight, with Apple, Google and Samsung posting support instructions, CBS and Yahoo report.

Daylight saving time is scheduled to return March 14, 2027 — a late date because March begins on a Monday — and would end next year on Nov. 7, per NBC News.

The bigger question is whether the Senate acts before the bill expires in early January. Yahoo and CBS report the legislation would also let states opt out entirely, meaning even if it passes, Americans could still be changing clocks in some places.

Whether Trump's public pressure campaign on Cotton moves the Senate, or the whole effort restarts with a new Congress, should be resolved within weeks.