With Bernie Sanders and Hillary Clinton engaged in a final push to woo voters ahead of Saturday's Democratic caucus in Nevada, two religious groups will be sidelined on caucus day.

Religious Jews and Seventh-day Adventists both observe the Sabbath, a holy day of rest, on Saturdays.

Members of Nevada's Jewish community call the timing of Saturday's caucus "disappointing," as the 11 a.m. start time precludes observant Jews from participating. Sabbath is observed from sundown Friday through sundown Saturday.

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"I believe everyone should be counted," Rabbi Shea Harlig of Chabad of Southern Nevada said. "They don't want to go through the effort to make the accommodations."

In 2012, Republicans also caucused on a Saturday, yet an alternate time was arranged after sundown. Harlig noted that Las Vegas-based casino magnate Sheldon Adelson, a major GOP donor, possibly influenced state Republicans' decision to accommodate observant Jews. Republicans will caucus on Tuesday. State Democrats, Harlig suggested, possibly lack an individual with comparable wealth or clout to spur a time change.

Rabbi Bradley Tecktiel, the community relations council chairman at the Jewish Federation of Las Vegas, criticized the "insensitive response" of the state Democratic party. Alternate arrangements were proposed to state Democrats, he said, yet those requests were rebuffed.

Democratic presidential candidate Bernie Sanders is a secular Jew, while Republican presidential candidate Ben Carson is a Seventh-day Adventist.

"This is the democratic process," Tecktiel said. "Jews take it very seriously that we can participate in this country."

According to the Nevada secretary of state's website, absentee voting is not permitted during a contest; one must be physically present at a caucus location.

In a statement released last week, the Orthodox Union, among the U.S.' largest Orthodox Jewish groups, asked Nevada Democratic officials to "ensure that all Nevadans can participate in the important presidential caucus." The statement continued: "We must protect religious freedom."

By Friday evening, a spokesperson for Nevada's Democratic party had not returned CBS News' calls or emails for comment.