Burlington, Iowa (CNN) Hillary Clinton, her voice softened and tone contemplative, stressed to Iowa voters in Burlington on Wednesday night that while this campaign has not been easy, she knows how to "what it is like to be knocked down but not knocked out."

The race in Iowa, which is nearing its final sprint towards the February 1 caucuses, has been tightening in the last few weeks, and the pressure is mounting on Clinton to avoid a loss in the first in the nation caucus. The pressure on her Iowa operation was ratcheted up even more on Tuesday when a CNN/WMUR New Hampshire poll found Clinton down by 27 points to Vermont Sen. Bernie Sanders, her unexpectedly stout opponent.

Clinton opened her first appearance since the poll by focusing on her own personal struggles and ability to bounce back from tough times.

"I have had a few hard times. I don't know anybody in this audience that have not had their own share," Clinton said. "It is not whether you get knocked down, it is whether you get back up. And I have gotten back up time and time and time again."

The tone was surprising to many in the audience, including some of Clinton's aides who were taken by their candidate's candor about her personal struggles.

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