The 45th POTUS sat down for an interview with Sharyl Attkisson on 'Full Measure' ... where she asked him point blank if he sees a 2028 run in his future or if this election's his last dance.

DJT says, "No, I don’t. I think… that will be it. I don’t see that at all. Hopefully, we’re gonna be successful."

So, this may be Republicans' last chance to put Donald in the White House ... which won't come as much of a shock to many considering Donald's age.

By the time the 2028 election comes around, Trump will be 82 -- several months older than even Joe Biden will be when he officially exits office in January of next year ... so, it'd be hard to see him readying for a four-year term as the oldest prez in history.

Of course, if he wins, then Trump can't run in '28 anyway ... at least, not without a change to the U.S. Constitution which limits presidents to two terms.

Trump's looking to become the first president since Grover Cleveland in 1892 to win two non-consecutive bids as president ... a tall task, especially with national polls showing Kamala Harris leading the former prez by the slimmest of margins.