Story highlights Democratic candidates for president took part in a town hall discussion in Iowa on Monday

Errol Louis: Hillary Clinton faces stiff competition from Sen. Bernie Sanders and Martin O'Malley

Errol Louis is the host of "Inside City Hall," a nightly political show on NY1, a New York all-news channel. The opinions expressed in this commentary are solely those of the author.

(CNN) There's a reason Hillary Clinton is leading her nearest Democratic rival by over 10 percentage points in the latest national polls, and she showed why again at the Iowa Democratic town hall on Monday night. Clinton was in turns humorous, determined, knowledgeable and earnest, leaving no doubt that she has a level of political and public policy expertise that few American politicians can match.

"If it was easy, there wouldn't be any contest," she told a young woman in the course of explaining why so many Republicans seem bent on stopping her at all costs. "I've been on the front lines of change and progress since I was your age."

Errol Louis

Clinton even embraced the fact she draws attacks from right-wingers. "They throw all this stuff at me. And I'm still standing," she said, comparing the civility of the night's discussion with the Republican slugfest. "The other side is not talking issues, it's talking insults," she said.

Tough competition

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