Democratic presidential nominee Joe Biden said in an interview airing Sunday that he is "absolutely" open to serving two terms if elected, despite previously calling himself a "transition candidate."

Biden argued that the "transition candidate" comment meant that he would be someone who would help pave the way for a new generation of Democratic leadership.

The comment did not mean he would serve as a one-term president, he told ABC News.

"In any state where we have competitive people running for the Senate and the House and the legislature, it's important the Democratic Party invest there," Biden told ABC's David Muir. "So [what] I want to do is make sure when this is over, we have a new Senate, we won back statehouses, we’re in a position where we transition to a period of bringing people up to the visibility that they need to get to be able to lead nationally. And that's about raising people up. And that's what I'm about."

TRUMP TO REVEAL CORONAVIRUS 'BREAKTHROUGH' THERAPEUTIC, WH PRESS SECRETARY SAYS

Both President Trump and his campaign have stepped up their attacks against Biden's mental fitness. Biden, however, challenged the president to take a closer look.

"Watch me, Mr. President. Watch me. Look at us both, what we say, what we do, what we control, what we know, what kind of shape we're in," Biden said, referring to his running mate, Sen. Kamala Harris. "I think it's a legitimate question to ask anybody over 70 years old whether or not they're fit and whether they're ready. But I just -- only thing I can say to the American people, it's a legitimate question to ask anybody, watch me."

If elected, Biden would be 78 years old on Inauguration Day in January. If he ran again in 2024 and was re-elected, he would be age 82 on Inauguration Day and would hand over the reins to a new president at age 86.

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