Story highlights Clinton and Trump are both watching debate videos of one another

Trump has huddled with his advisers, including RNC chairman Reince Priebus

Washington (CNN) Donald Trump is watching videos of Hillary Clinton's past debate performances -- including both her highlights and lowlights -- ahead of their first debate Monday.

A source familiar with his preparations described Trump's preparation, which has been described as far more minimal than Clinton's, who is currently off the campaign trail to practice before the highly anticipated, nationally broadcast event. Trump has huddled with his closest advisers in his prep session, including Republican National Committee Chairman Reince Priebus, who sat in on last weekend's meeting, the source said. Priebus will join Trump again this weekend.

Clinton is similarly watching tape of Trump's Republican primary debates, according to several people familiar with her debate preparation. She took notes on what agitated him, particularly in his exchanges with rival Ted Cruz, and studied his style.

To knock Trump off his game, people advising Clinton have been looking for a one-line retort that will be a memorable moment from the contest.

But Democrats worry the first debate will give Trump a chance to show a more moderate, controlled side, while millions of people watch, possibly for the first time. This, according to people who have recently talked with the former secretary of state, is not lost on Clinton.

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