(CNN) — Competing town halls on Thursday night will have President Donald Trump and his Democratic challenger, Joe Biden, facing tough questions from voters, but viewers at home will be forced to choose which one to watch live.

At 8 p.m. ET, Trump is set to take questions from voters on NBC. Biden will be doing so at the same time on ABC. The Trump town hall lasts an hour; Biden’s lasts 90 minutes.

They were scheduled after the Commission on Presidential Debates canceled Thursday night’s planned town hall-style debate between Biden and Trump in the wake of Trump’s coronavirus diagnosis. The commission sought to shift that debate to a virtual format; Trump rejected the change.

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Instead of getting the opportunity see the two candidates onstage together, viewers will have to pick one or the other.

Since the town halls won’t draw nearly the ratings of a presidential debate, what will matter most is whether either event delivers a moment big enough to change the trajectory of the race as millions of Americans are voting early. National and swing-state polls show that a trailing Trump desperately needs such a moment; Biden does not.

Here’s what to watch in Thursday night’s dueling town halls:

Trump and the virus

The President’s town hall with NBC News will be the first time he will be pressed at length and not on a friendly conservative outlet about his personal bout with the virus that has reshaped his reelection bid.

Trump has made a number of dubious claims about his recovery from the virus, including claiming that an experimental drug cocktail created by Regeneron that he received is a “cure” for the virus, although there is no data even suggesting this. The President has also claimed to be immune to the virus, although studies show it is possible to be reinfected and doctors say it’s not clear how much immunity people have after recovering from infection.

How the President handles pointed questions from the moderator and voters about the virus will likely determine how successful he is in the format, along with how his answers line up with the reality facing Americans dealing with the pandemic.

The virus, according to scores of polls and interviews with voters across the country, is the most important issue on the minds of Americans right now, and Trump’s handling of the pandemic has proved to be a weight on his reelection bid.

Biden and Trump weigh in on Capitol Hill’s stimulus fight 

The US economy is in a Covid-fueled shambles. Americans are waiting in food lines. States are falling deeper into budgetary holes. But the response from Congress has been — well, there hasn’t been one in a while.

Both Trump, who’s sent mixed signals on stimulus talks, and Biden, who’s yet to definitively weigh in, will likely be asked for their takes on what should happen next.

House Democrats passed a $2.2 trillion relief package earlier this month. But that’s a no-go in the GOP-controlled Senate. Meanwhile, Trump first tweeted that negotiations were off “until after the election,” before quickly reversing himself and challenging his own party. By Tuesday, his message was, “STIMULUS! Go big or go home!!!” He’s now supporting a $1.8 trillion deal.

The question for Trump: Which statement is operative on Thursday?

It’s a sticky wicket for Biden, too, in large part because of the divisions in the Democratic House caucus. Speaker Nancy Pelosi has so far rejected the White House’s offer. But not all of her members agree with that decision — one she vigorously defended in a now-viral interview with CNN’s Wolf Blitzer.

The question for Biden: Whose side does he take? So far he’s only criticized Trump as “reckless” and inconsistent.

The Supreme Court and health care 

For anyone who’s watched more than a few minutes of the Democratic senators questioning Supreme Court nominee Amy Coney Barrett, the party’s strategy should be pretty obvious: Convince the public that her confirmation vote amounts to a referendum on Obamacare.

Barrett hasn’t officially weighed in on the law or the case that could strike it down — which is scheduled to be heard a week after the election — but Democrats have been arguing that Trump’s opposition is evidence enough that she, as his selection, would do just that.

While Barrett has kept mum on her views, Trump’s are well known.

On Thursday, he’ll probably get asked if he expects Barrett, if confirmed, to vote to kill Obamacare. Unless he pleads ignorance, it could make for a sticky situation for the nominee, who has said she did not discuss the case with the President. It’s hard to imagine that Trump’s comments on this don’t cause an uproar.

As for Biden, he’s a good bet to continue hammering the party line. Though this conversation will lead him into some waters he’s sought to avoid: court packing.

The questions Biden has ducked 

For two weeks, Biden has refused to offer a clear, detailed answer to the question of whether he would support a progressive push to add seats to the Supreme Court, where Barrett’s confirmation could soon give conservatives a 6-3 majority.

“I’m not a fan of court-packing, but I don’t want to get off on that whole issue,” Biden told CNN affiliate WKRC in Cincinnati. “I want to keep focused. The President would love nothing better than to fight about whether or not I would, in fact, pack the court or not pack the court.”

Biden’s political calculations are clear: Polls show he’s ahead of Trump; he benefits from the status quo and could be hurt by a round of headlines featuring him taking a position that either alienates progressives or gives Trump a new opening to attack.

Biden has acknowledged in recent days that he’s trying to run out the clock on the question of court-packing. Voters will “know my opinion on court-packing when the election is over,” he told reporters last week in Arizona.

Another question he has not directly answered is whether he would seek to abolish the Senate’s 60-vote threshold to break the filibuster. The questions he has ducked seem small compared with those Trump has refused to answer — such as what his long-promised health care plan entails and what his tax returns show — but are important to liberals who think Senate Republicans have spent years stacking the deck against Democrats procedurally, making it difficult to enact new policies under a Democratic-led Congress and keep the courts from striking them down.

The former vice president has not faced the sort of sustained questioning on either issue that could take place in Thursday night’s town hall format. 

The clock is running out

Trump is trailing Biden and time is running out.

That is arguably the most pressing issue facing the President right now and, as the number of days left in the campaign ticks below 20, the number of hig-profile opportunities for him to make a final pitch to voters is dwindling.

Thursday’s town hall will likely be watched by millions — offering Trump a needed platform — but the viewership will almost certainly pale in comparison with what a general election debate with Biden, which would have aired across all networks, would have provided the President. The first debate between the two men was watched by more than 73 million Americans.

View Trump and Biden head-to-head polling.

That lack of high-profile events puts increased pressure on town halls like the NBC and ABC events, with just one more debate scheduled in the closing weeks of the election.

The reality is, however, that because Trump is trailing, he needs these events more than Biden does.

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