Sen. Jeff Sessions on Sunday sought to justify Donald Trump's call for poll watchers, defending Trump's claim that he'll lose Pennsylvania in the general election only if "cheating goes on."

"Every party goes out in advance of the election and they call on poll watchers and those kind of things to make sure they're not cheated out of an election. That just really helps create integrity in the system," Sessions, a top Trump adviser, said on ABC's "This Week." "There's cheating in every election."

Trump has a page on his website seeking poll watchers to help him ferret out what he says will be an attempt by Hillary Clinton to steal the election.

At a rally in Altoon, Pa., on Friday, Trump said only voter fraud would prevent him from winning the Keystone State.

Pennsylvania this year is considered a key swing state, though it has voted Democratic in the past six presidential elections.

Sessions explained that Trump and his campaign believe they can win Pennsylvania.

"He's been neck and neck and Republicans haven't won Pennsylvania in many, many years," the Alabama Republican said in the ABC interview. "So he's going after Pennsylvania. He believes he can win Pennsylvania. And he's going to work at it."

Sessions then said that "too much" has been made out of Trump's cheating comment.

"I think he believes — what he was saying is, it's going to be a very close election. He believes he's going to win Pennsylvania," Sessions concluded.