Many Democrats Are Worried Trump Will Beat Biden. This One Isn’t.

Simon Rosenberg was right about the congressional elections of 2022. All the conventional wisdom — the polls, the punditry, the fretting by fellow Democrats — revolved around the expectation of a big red wave and a Democratic wipeout.

He disagreed. Democrats would surprise everyone, he said again and again: There would be no red wave. He was correct, of course, as he is quick to remind anyone listening.

These days, Mr. Rosenberg, 60, a Democratic strategist and consultant who dates his first involvement in presidential campaigns to Michael Dukakis, the Democratic presidential candidate in 1988, is again pushing back against the polls and punditry and the Democratic doom and gloom. This time, he is predicting that President Biden will defeat Donald J. Trump in November.

In a world of Democratic bed-wetters, to reprise the phrase used by David Plouffe, a senior political adviser to Barack Obama, to describe Democratic fretters, Mr. Rosenberg is the voice of — well, whatever the opposite of bed-wetter is these days. He even has a Substack newsletter offering insights and daily reassurance to his worried readers — “Hopium Chronicles,” the name taken from what the pollster Nate Silver suggested he was ingesting back in 2022.

I talked to Mr. Rosenberg about what it feels like to be an outlier in his own party, and why he sleeps so well at night while so many of his fellow Democrats are plotting their moves to Paris after November. This conversation has been edited for clarity and length, and because Mr. Rosenberg — God love him — likes to talk about this subject. A lot.

Good morning, Simon. And, first things first, thank you for doing this.

Any opportunity I have to talk about the good works of Joe Biden and the Democrats — how could I turn that down?