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 his own. View more opinion articles on CNN.

(CNN) The CNN town hall with Bernie Sanders on Monday night showed the Vermont senator picking up where he left off in 2016: Calling for higher taxes on the wealthy, single-payer health care and a dramatic expansion of government support for programs including pre-kindergarten and university education.

Errol Louis

If much of what Sanders said sounded familiar, it's because many policies that sounded radical and new in 2016 have become mainstream Democratic positions. It's not that Bernie went centrist; instead, the center moved toward him. That is how the Vermont senator raised $10 million in the week after announcing his candidacy for the 2020 nomination, and it's why he polls near the front of the pack of contenders running for the Democratic nomination.

So the town hall sounded like a walk through the standard Democratic talking points, which isn't particularly exciting. Sanders promised to do something about the millions who struggle in poverty. He vowed to slap new taxes on "the billionaire class" to cover the cost of relief for the poor.

The pharmaceutical industry is "the most greedy entity in this country today," he said , with it raking in $50 billion in profits last year while one in five Americans can't afford vital medicines like insulin. (Sanders called for laws to allow Medicare to negotiate lower prices with pharmaceutical companies).

Thanks to Sanders' attention to these issues in 2016, now all Democratic candidates must promise to tackle income inequality, the high cost of health care and the stranglehold that monied interests hold over Congress. But that leads to a potential problem for Sanders: other candidates, like Sens. Elizabeth Warren, Kamala Harris and Cory Booker can present an identical analysis while offering more sizzle and pizzazz than Sanders can muster with his professorial style.

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