The odds are increasing that America's 2024 presidential election will be a re-run of 2020 -- President Joe Biden vs. former President Donald Trump.

In the Republican Party, Trump now leads his nearest challenger, Florida Gov. Ron DeSantis, by 52-18, while Biden leads Robert Kennedy Jr., maverick son of the late Senator Robert Kennedy, by 63-14.

DeSantis, once expected to challenge Trump seriously for the Republican nomination, is rebooting his listless campaign, while other declared Trump rivals have yet to gain traction.

Kent Calder. (Kyodo)

Betting polls now assign both Trump and Biden a 60 percent probability of becoming their party's next presidential nominee. Although the prospects now appear strong that Biden and Trump will represent America's two major parties in 2024, the American people in general seem markedly uneasy about that prospect.

Indeed, close to half of the electorate would reportedly consider a third-party candidate if the 2024 presidential election becomes a mere re-run of the 2020 Biden-Trump contest.

That group of skeptics includes, according to NBC News, 58 percent of Hispanics; 52 percent of African Americans; 57 percent of young voters under 35; 45 percent of Democrats overall; and 34 percent of Republicans.

This ambivalence among prospective American voters about a Biden-Trump re-run reflects not only disillusionment with the candidates themselves, but an even broader distancing from the two major parties.

Independents (41 percent of the electorate) now significantly outnumber both Republicans (28 percent) and Democrats (28 percent). And the share of such non-aligned voters has been steadily rising -- from 35 percent in 2000. Among younger millennial and Generation Z voters born since around 1980, the share of declared independents is almost half.

Broad dissatisfaction with the looming Biden-Trump match-up naturally creates a potential constituency for third parties. These have rarely prospered in American presidential politics, with its structural bias toward a two-party system.

Yet their electoral share has been slowly increasing in recent years, and third parties have at times fatefully influenced the balance of power between Democrats and Republicans, due to America's distinctive, state-winner takes all electoral vote system.

In 2000 the Green Party, led by Ralph Nader, siphoned votes away from Al Gore in Florida, leaving George W. Bush with a 600-vote victory; in 2016 Jill Stein's Green Party candidacy similarly helped swing key states such as Michigan, Wisconsin, and Pennsylvania to Trump, leading to Hillary Clinton's defeat.

Approaching the 2024 election, the Green Party, with well-known Afro-American activist and university professor Cornell West as a leading candidate, is opposing President Biden's defense and social welfare policies from the left. This is compounding the progressive pressure from Kennedy inside Democratic ranks.

The Greens have already gained ballot access for 2024 in 18 states, including Wisconsin and Michigan, major swing states that Biden carried only narrowly in 2020.

Additionally, the No Labels NGO, founded in 2010, shows the prospect of possibly also nominating a presidential candidate for 2024. No Labels is supported by an expanding political operation, based on Connecticut Avenue in the heart of Washington, D.C., and backed by senior executives at Loews, Fluor, Freeport LNG, Panera, and other major firms.

No Labels held a major New Hampshire rally in late July, keynoted by Democratic Senator Joe Manchin (D-West Virginia) and former Republican governor of Utah Jon Huntsman.

Both see more attractive prospects for themselves on the national stage than at home, with Manchin facing a tough Senatorial election fight, and Huntsman having recently lost in an attempted return to the Utah governorship, after a promising presidential primary run in 2012 and a distinguished subsequent diplomatic career.

Huntsman served as U.S. Ambassador to Singapore, China, and Russia, under Presidents Bush, Obama, and Trump respectively.

Virtually all political indicators suggest that the 2024 presidential race will be a close one between the two major parties, with President Biden currently holding a narrow advantage of less than 1 percentage point if Trump is the Republican nominee.

Given the prospective closeness of the 2024 race, and the volatility of an electorate half populated by independent voters with marginal commitment to either the candidates or the parties, what sort of impact might third parties actually have on the election?

The Green Party, as in 2000 and 2016, would likely undermine Democratic chances, especially in swing states with large college-student populations, such as Wisconsin. That could make nominating decisions by No Labels crucially important to the ultimate electoral outcome next November.

Some conservative commentators, such as Karl Rove, former political advisor to President George W. Bush, have argued that a sufficiently conservative No Labels nominee could build on frustration with Trump inside the Republican Party, and substantially influence election outcomes.

Even if a No Labels candidate were not electable, figures such as Manchin or Huntsman could draw significant support away from Trump in the Midwest, Appalachia, and the Intermountain West.

No Labels could thus, depending on their candidate, either counter-balance the left-oriented Green Party, thus aiding Biden, or compound the challenge that it poses to the president's re-election.

As if third-party challenges were not enough, both Biden and Trump still face undeclared potential dark-horse challenges within their own ranks.

Apart from existing declared candidates, Virginia Gov. Glenn Youngkin, a wealthy former co-chairman of the Carlyle Group, is thought to be considering a run on the Republican side.

And California Gov. Gavin Newsom, a long-time rival of current Vice President Kamala Harris in California politics, is given a 14 percent and rising chance, in national betting polls, of being the Democratic nominee.

So a "third way" in presidential politics, beyond Biden and Trump, is being ever more actively debated, amidst broad-based if still quiet disillusionment with the prospects of a 2020 re-run.

(Kent E. Calder is the director of the Edwin O. Reischauer Center for East Asian Studies at the Johns Hopkins School of Advanced International Studies in Washington.)


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