Kamala Harris to make surprise appearance on 'Saturday Night Live.' How to watch.

There may not have been an October surprise, but Vice President Kamala Harris may pull off a big one Saturday night with the election just three days away.

Harris will make a surprise appearance on "Saturday Night Live," on the final Saturday ahead of the Nov. 5 election. She is expected to be in the cold open sketch at the start of the show, according to an official who spoke to the pool of reporters traveling with the vice president. In recent weeks, the opening sketch of the show has focused on the presidential election.

Reporters traveling with the vice president rolled up to Rockefeller Center, where the 50-year-old sketch comedy show is filmed, just after 8 p.m. EST and were holding in the crew cafeteria for "SNL" shortly after arriving.

In the final days of the campaign, Harris has appealed to undecided voters as she and Republican Donald Trump are locked in a razor-thin race to the White House, with the two candidates in a dead heat in most of the seven swing states.

Harris on Saturday campaigned in two key swing states: Georgia and North Carolina. She was set to fly to Detroit Saturday evening, where she is scheduled to have events Sunday in the swing state of Michigan. However, Air Force Two landed at LaGuardia Airport in an unannounced stop in New York City on Saturday evening.

Comedian Maya Rudolph, an alum of the show, returned last month to play Harris for "SNL" in the run-up to Election Day. Harris has previously said that Rudolph's impersonation of her is "so good."

She’s so good,” Harris said during an interview on "The View" last month. “She had the whole thing – the suit, the jewelry, everything. Wow, the mannerisms."

How to watch

The episode will be aired live Saturday on NBC at 11:30 p.m. ET/8:30 p.m. PT. Viewers can also stream it the following day on Peacock.

Who is hosting?

John Mulaney will host the show and Chappell Roan is the musical guest.

Chappell Roan, who rose to fame this spring, declined to endorse Harris in the election but later said she would vote for her. The singer-songwriter expressed dissatisfaction with how Democrats have handled Israel’s war in Gaza and their stance on trans rights.

Presidential contenders have appeared on 'SNL' before

Harris is not the first presidential contender to appear on the show.

Both Trump and Democrat Hillary Clinton appeared on the show in 2015. Barack Obama also dropped in on the show in 2007.

But those appearances were anticipated in advance, the candidates didn’t pop in days before the general election.

(This story was updated to add new information.)

This article originally appeared on USA TODAY: Kamala Harris to make surprise appearance on 'SNL': How to watch