ATLANTA — Entering the first debate, the presidential race is already remarkably defined and yet still unpredictable.

President Biden and former President Donald Trump are both disliked by broad swaths of the electorate and still have clear paths to victory just over four months from Election Day.

Those paths, however, are littered with potential pitfalls and obstacles — including third-party and independent rivals and public fretting over age and temperament — that add to the lingering sense of uncertainty hanging over the race.

“The race has been stagnant because both candidates are known quantities,” said Patrick Murray, director of the Monmouth University Polling Institute. “The issues — whether inflation or immigration or abortion — are just outward expressions of what really underlies voters’ motivations — fear of change and uncertainty about the future.”

The good news for Mr. Biden is polls show a tightening horse race.

He has post-Roe political tailwinds on his side. He benefits from a deep-seated dislike of Trump which helps him with listless votes who might view him as the lesser of two evils in an election where many voters are not enamored with their choices.

Running against a convicted felon also doesn’t hurt. Mr. Trump is set to be sentenced on July 11 and could face jail time or home confinement.

Still, there are ominous signs for Mr. Biden.

As an 81-year-old, the former vice president and longtime Delaware senator’s verbal miscues and fragile appearance have sparked a national debate about his mental chops, provided fodder for his critics and muddied his reelection message.

The situation has made it harder for him to dispel concerns about whether he has four more years in the tank and enough mojo left to fire up core Democratic constituencies, namely young and minority voters who are ho-hum about him.

“A key to his reelection will be whether he can bring back home those wavering voters,” said Mark J. Rozell, a political science professor at George Mason University.

Indeed, Mr. Biden could kiss his reelection hopes goodbye if Black voters do not flood the polls for him in places like Detroit and Philadelphia.

The 78-year-old Trump has led in the battleground states and has shown signs of eating into the Black and Hispanic vote.

Buoyed by the unyielding support of MAGA loyalists ready to run through a wall for him, Mr. Trump has emerged relatively unscathed from his conviction for falsifying business records to cover up hush money payments to a porn star in 2016.

Team Trump saw a surge of donations following his conviction.

Americans trust him more on key issues, including the economy and immigration, which Mr. Trump has made the centerpiece of his campaign.

Polls also have shown that three-plus years into the Biden experience more voters take a nostalgic view of Trump’s time in office. A Washington Post survey released this week found that more swing state voters trust Mr. Trump to combat threats to democracy.

Still, Mr. Trump can’t shake doubts about whether his unconventional behavior and pugilistic instincts will cripple his attempts to woo fence-sitters. Can he set that all aside, and deliver a disciplined, Reaganesque, message centered on the question: Are you better off than you were four years ago?

“The challenge for Trump is to not remind people — especially the people in the middle — that he will be causing them stress every single day and so his challenge is to draw a clear comparison between the Biden four years and the Trump four years,” said David Paleologos, director of the Suffolk University Political Research Center. “That is it. It is that simple.”

The race dynamics are encapsulated in a recent Marquette Law School Poll that showed Mr. Biden has seized the lead from Mr. Trump among registered voters in Wisconsin.

It also showed something that activists have come across on the ground: voters are far less enthusiastic about the election compared to this point in 2020,

“This is one of the least engaged electorates I can remember in recent history,” said Matt Moreno, chair of the Waukesha County Democrats in Wisconsin. “A lot of regular voters are not dialed in yet.”

Mr. Trump’s supporters, however, are intensely engaged.

He holds a 61% to 39% edge over Mr. Biden with voters who are “very enthusiastic” about voting this fall, while Mr. Biden has a 65% to 33% edge over Mr. Trump with voters who are “not at all enthusiastic.

The survey also underscored the impact third-party and independent candidates could have on the race in battleground states.

In that case, Mr. Trump has a 43% to 40% lead over Mr. Biden. Independent candidates Robert F. Kennedy Jr. and Cornel West garnered 8% and 4% support, respectively. Libertarian Chase Oliver and Green Party candidate Jill Stein each receive 2% of the vote.

According to a running tally from the New York Times, the Green Party, which expects to tap Ms. Stein as its nominee at its August convention, is on the ballot in Arizona, Michigan, North Carolina, and Wisconsin.

Mr. Kennedy is on the ballot in Michigan and says he has filed the signatures needed to gain ballot access in Nevada and Pennsylvania.

Mr. Oliver, who won the Libertarian nomination in May, is set to appear on the ballot in Arizona, Georgia, Michigan, Nevada, North Carolina and Wisconsin.

Mr. West has yet to qualify for the ballot in a battleground state.

• Seth McLaughlin can be reached at smclaughlin@washingtontimes.com.