(NewsNation) — A slew of polls in the must-win battleground state of Pennsylvania show a tight race between Vice President Kamala Harris and former President Donald Trump ahead of the Nov. 5 presidential election.

Should Democrats be nervous? One U.S. senator doesn’t think so.

Although both candidates are within the margin of error, Sen. John Fetterman, D-PA, said his party expected the close polling numbers.

“This is exactly what I’ve been saying, the same thing since 2016,” Fetterman said on “The Hill Sunday with Chris Stirewalt.”

In 2016, Trump beat Democratic presidential nominee Hillary Clinton, who previously served as President Barack Obama’s secretary of state.

“I’ve been saying that when Trump is on the ballot, it’s going to be very, very close. That’s what I said in 2016, and of course, Secretary (Clinton) lost,” Fetterman said.

The senator has been campaigning across his home state in places where Donald Trump won by a wide margin, such as Somerset County where he won by 56 points in 2020.

“For Democrats, the key is in the margin,” Fetterman said. It’s never about turning Somsert red. That’s never going to happen and certainly not in my lifetime probably, but what I will say is that we can’t afford to lose 80/20 times 57.”

Pennsylvania has 57 counties. One of those is Erie County where Trump carried the county by about 2,000 votes in 2016. Biden carried the county by about 1,500 votes in 2020.

Fetterman attributes Clinton’s loss to her focusing “too much” on the populous cities of Philadelphia and Pittsburgh.

“There are a lot of other parts in Pennsylvania,” he said, urging his former campaign manager to encourage Biden to campaign in Erie in the last presidential election.

“Erie picks the winner of Pennsylvania, and then Pennsylvania picks the president because Pennsylvania is a smaller version of America in terms of urban and rural and suburban,” Fetterman said. “It’s the ultimate purple state.”

Elon Musk, the owner of X, SpaceX and Starlink, has been campaigning for Trump, giving another boost to his bid for president.

“Some people see (Trump) as Tony Stark.”

Twnety-three days remain until voters will cast their votes.