Four years before the next presidential election, Democrats have two formidable would-be challengers to Donald Trump. One is a successful governor and the other a popular politician. Both have a problem: In 2020, California’s Jerry Brown will be 82 and Joe Biden will be an ex-vice president nearing 78. The U.S. may be graying, with Trump the oldest newly elected president ever, but not that much.

Biden and Brown offer instructive examples for their down-and-out party. Other than President Barack Obama, no Democrat offers a more compelling message and record than these two.

I believe Biden would have trounced Trump in November in both the popular vote and Electoral College. (Though I doubt that the vice president, who chose not to run while grieving for his son, Beau, who died of cancer, would have won the nomination.)

Democrats should listen to him as they debate whether they should double down on their success with young voters, members of minority groups, suburbanites and college-educated professionals, or focus instead on winning over some of the working-class whites who went decisively for Trump. Biden argues that this is a false choice — that Democrats need an economic agenda that appeals to both.

He has a long progressive record on civil rights and women’s issues. He pushed his boss, President Obama, to support gay marriage. Yet he’s also passionate about helping struggling workers. During the campaign, he complained that Hillary Clinton and other Democrats failed to appeal to middle- and working-class white voters. Biden knew their votes would be needed to carry places like Wilkes-Barre, Penn., a Democratic city that went for Trump.

Brown has become one of the best governors. Although California is more liberal than the U.S. as a whole — Clinton carried the state by almost 4.3 million while losing the rest of the country by 1.4 million — his achievements, too, defy conventional labels. The son of a governor and once a Jesuit seminarian, Brown was California’s boy-wonder governor in 1975 when, at age 36, he began his first two-term stint. He’ll reach 80 next year in the final of his second two terms, far more successful than before.

He rescued California from bankruptcy by restraining spending, persuading voters to approve a tax hike on the wealthy and setting aside a rainy-day fund for the next downturn.

A champion of socially progressive causes, he’s a strong environmentalist. He has even warned Trump that California will launch satellites to monitor greenhouse-gas emissions if Republicans end climate-science work by the National Aeronautics and Space Administration. But he’s been also defied some greens by supporting fracking, and business is thriving under his stewardship.

Today’s Jerry Brown is more politically appealing than the 1970s version, having added a sense of humor and abandoned a fondness for the grandiose schemes that inspired the nickname “Governor Moonbeam.”

Brown, born to political royalty, and Biden, son of a car salesman, have profoundly different political personas and vantage points. Democrats cannot turn to either one to lead them out of the wilderness in 2020. But these septuagenarians, each with more than four-and-a-half decades in public life, are current and relevant. Democrats should listen to them.

Albert R. Hunt is a Bloomberg View columnist.