WASHNGTON (CBSNewYork/AP) — Chelsea Clinton is surprised her mother Hillary is slipping in the polls.

On the TODAY show Tuesday, Clinton said she’s “my hero’ and said she believes that as more Americans get a chance to hear from Hillary Rodham Clinton they will understand “why I believe so strongly that she would make a great president.”

Recent polls suggest Vermont Sen. Bernie Sanders has a lead over Clinton in New Hampshire and is closing the gap in Iowa.

In Iowa, Clinton’s 24 point lead in July has been cut more than half to just 11. Clinton has been dogged by constant questions about her private email server while she was Secretary of State. She won the 2008 New Hampshire primary and campaigned there on Saturday.

In Monmouth University’s first poll of the 2016 New Hampshire Democratic primary, Bernie Sanders has a 7 point lead over Hillary Clinton among likely voters.

When asked what Hillary is like as a grandmother, Chelsea Clinton said her mom is always game for singing “The Wheels on the Bus” to baby Charlotte and is helping her learn to walk.

When asked whether her mom was a good singer, Chelsea laughed and said, “Not at all.”

Clinton was interviewed about her new book, “It’s Your World: Get Informed, Get Inspired & Get Going!”

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