A congressional effort to make daylight saving time permanent is facing growing resistance in the Senate, where lawmakers remain divided over concerns about student safety, morning darkness, and the practical consequences of changing school schedules.

The House passed the Sunshine Protection Act in a 308-117 vote on July 14, with 193 Republicans and 114 Democrats supporting the measure. The legislation would eliminate the annual spring and fall clock changes by keeping daylight saving time in place throughout the year.

However, the bill remains stalled in the Senate. Majority Leader John Thune, R-S.D., who voted against the proposal in the Senate Commerce Committee, has acknowledged that lawmakers lack the consensus needed to move it forward.

President Donald Trump has pressed Republican senators to act on the legislation. On Oct. 3, he urged Arkansas residents to contact Sen. Tom Cotton, R-Ark., and posted the senator's cellphone number amid the dispute.

Cotton has argued that permanent daylight saving time could leave children traveling to school in darkness during winter mornings. He pointed to the country's previous experiment with year-round daylight saving time, which Congress ended after concerns about late winter sunrises.

Other lawmakers have raised similar objections. Sen. Roger Wicker, R-Miss., has warned about safety risks for students in northern and rural communities who board school buses early in the morning. Sen. Mark Kelly, D-Ariz., has also opposed permanent daylight saving time, though he favors keeping standard time year-round instead.

The timing of sunrise is a central issue in the debate. AccuWeather projections cited in the discussion indicate that on Jan. 15, the sun would rise at 8:35 a.m. in Kansas City and 8:51 a.m. in Billings, Montana, under permanent daylight saving time.

The Centers for Disease Control and Prevention reported that the average public high school start time was 7:59 a.m. during the 2011-12 school year, meaning many students begin their day well before sunrise during winter months.

Supporters of the legislation argue that schools could address the problem by starting classes later. Research has associated later school start times with longer sleep, improved attendance, better grades, and fewer motor vehicle crashes among teenagers.

But changing school schedules presents its own challenges. Districts must account for parents' work hours, transportation arrangements, after-school activities and athletic schedules. In some communities, later dismissals could also complicate coordination between neighboring schools.

Advocates for later starts have warned that keeping daylight saving time year-round without adjusting school schedules could leave even more students traveling in darkness. School administrators, meanwhile, have cautioned that shifting the school day can affect families and school operations well beyond the morning commute.

Sen. Rick Scott, R-Fla., has said he is working to secure a Senate vote during the post-election congressional session in November or December. Until then, the proposal's future remains uncertain.

Most Americans are scheduled to return to standard time on Nov. 1, when clocks will move back one hour. Unless Congress acts, the twice-yearly time changes will continue.