Clinton visits battleground state twice in just 48 hours, joined by Beyonce, Jay-Z and LeBron James.

Ohio has for decades been America’s bellwether state. In most cases, historically, the candidate who wins Ohio wins the White House.

Right now, in the final days of the US election campaign, Ohio is a toss-up.

The latest local poll shows Democratic nominee Hillary Clinton ahead by just a single percentage point.

Factoring in the margin of error, it’s a statistical dead heat between Clinton and her Republican rival, Donald Trump.

Clinton’s lead in this state is so fragile that some people volunteering for her campaign tell me privately, they’re sweating it.

That’s why Clinton has visited Ohio twice in just 48 hours. On Friday, she held a #getoutthevote concert enlisting the help of celebrities Beyonce and Jay-Z. On Sunday, Clinton was back in the state, campaigning with the help of Cleveland Cavaliers basketball star, LeBron James.

Despite the star-studded endorsements, some of Clinton’s biggest supporters, like Terri Walton, remain nervous.

Walton is a cashier at Dave’s Supermarket in Cleveland, Ohio. Before standing in line for hours to hear Clinton and James speak, Walton worked a full shift at the supermarket.

“I told everyone in my line for my entire shift to get out and vote,” Walton told me. “I know it’s a close race. I can’t believe it. I don’t know how this happened.”

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Clinton’s campaign is wondering the same thing. Months ago, she seemed like the inevitable candidate ready for an ascension to the Oval Office.

But, Clinton’s self-inflicted missteps – including a secret email server in the basement of her home while secretary of state – have haunted her campaign.

The FBI in July cleared Clinton of wrongdoing. It’s a position the FBI Director, James Comey, reiterated on Sunday, after rocking the presidential election nine days ago by announcing that the agency was taking a second look at Clinton staff emails found as a result of an unrelated investigation

The announcement halted Clinton’s sprint to the election day finish line. It also zapped some of the enthusiasm of a core group of voters Clinton’s counting on – young African-American voters.

Early polling numbers indicate black voters aren’t turning out for Clinton like they did when Barack Obama was headlining the Democratic ticket.

Cleveland resident Derrick Elliott is concerned. Still Elliott and his friend, Verbon Pauldo, are optimistic.

“A lot [of black voters] will come out on Tuesday [to vote] and surprise people,” Elliott told me as he was waiting to hear what Clinton and the Cleveland Cavaliers basketball star had to say.

“I am taking this serious,” said Pauldo. “We got to vote. If we don’t vote for Hillary, Trump gets in.”

That prospect, they claim, is one they wish not to consider. Instead, Pauldo and Elliott believe black voters will ultimately “do the right thing”, as they say, and head to the polls on Tuesday.

That’s what Clinton is also counting on and she’s leaving nothing to chance. On Sunday, Obama was also stumping for Clinton. He implored black voters to turn out for Clinton in the same historic numbers as when he was the Democratic presidential candidate, in 2008 and 2012.

“All the progress we’ve made goes out the window, if we don’t win this election,” Obama said.

Using the verbiage of an athlete, Elliott agreed and summed up his message for fellow black voters.

“People better start playing,” he told me. “This election. It’s real.”