Welcome to the revenge of the moderates.

Since President Trump’s election, an activist liberal wing has taken hold of the Democratic Party. They’ve pushed bold economic, health care and environmental proposals. Some have embraced the term “socialist,” giving fresh fodder to Republican critics, and denounced the richest Americans and biggest corporations. And they’ve dominated the national conversation, from Representative Alexandria Ocasio-Cortez in Congress to Senator Bernie Sanders on the campaign trail.

But now, as the 2020 primary field comes into sharper focus, we’re starting to see a resurgence of more moderate, market-oriented Democrats, as they try to re-exert their power in a party they fear is courting political defeat by veering too far left.

Mr. Biden, a politician defined by the era of centrist Democratic politics, has his campaign plan nearly in place and seems to be moving toward entering the race in the coming weeks. Senator Michael Bennet of Colorado and other congressional moderates, like Representatives Seth Moulton of Massachusetts and Tim Ryan of Ohio, are making noise about launching their own presidential bids.

Those men, along with several other white male moderates who may enter the race, hope to provide a counterweight to the proposals of the Sanders-Warren wing of the party.

Of course, in one really big way, the liberals have already won by shifting the debate distinctly leftward. The conversation in the Democratic Party is around their ideas: a massive plan to fight climate change, a complete overhaul of the health care system, new taxes on the ultrarich.