For the second time Saturday, Joe Biden and Barack Obama held a drive-in rally in Michigan -- this time in Detroit -- and delivered a freewheeling event for an eager crowd that defied the campaign's calls for social distancing as they stood shoulder to shoulder near the stage. The event also featured audio problems during Obama's speech, but he took it in stride, joking with the crowd as it was fixed.

Biden was asked by a man in the crowd about the reunification of the 545 kids who were separated from their parents at the border. For the first time on camera, Biden said he'd set up a special commission to reunify the families if elected on "day one."

"The gentleman says, 'What about the 545 kids who were kidnapped?' That’s why I announced, immediately on day one, I’m setting up a special commission," he said. "We're gonna find those kids, we’re gonna unite them with their parents, we're gonna make sure their parents are together. What a total -- what a total embarrassment."

Obama again cast the 2020 race as the most important election "of our lifetimes," including his two previous successful runs for the White House.

"Three days, Detroit. Three days. Three days until the most important election of our lifetimes and that includes mine, which was pretty important," Obama said. "This Tuesday, everything is on the line. Our jobs are on the line. Health care is on the line. Whether we get this pandemic under control is on the line and the good news is on Tuesday, you can choose change. You can elect Joe Biden, you can elect Kamala Harris, you can choose a better America."

The event featured very little social distancing, the direct opposite of most Biden rallies, with a good portion of the crowd standing near the stage.

The campaign made at least a half dozen announcements asking people to return to their cars, but few obeyed, and no one stood 6 feet apart, crowding the press who were not penned off.

-ABC News' Molly Nagle, Johnny Verhovek and Beatrice Peterson

Timed just before his third rally Saturday, President Donald Trump released a memorandum on fracking and the oil and gas industry, which he told the western Pennsylvania crowd he signed on Marine One en route to the Butler County event.

Trump said the memo's intent is to "block any efforts to undermine energy production" in the state.

"So, in other words, if one of these maniacs come along and they say, we're going to end fracking, we're going to destroy the Commonwealth of Pennsylvania, you can say sorry about that," he said.

Trump used the memo to attack former Vice President Joe Biden over the Democratic presidential candidate's debate comment that he would "transition from the oil industry."

"If Joe Biden is elected, he will cancel our, and you know that, he's going to terminate, frankly -- a better word, terminate your energy industry and every job because they want to go to wind," Trump said. "They don't even want wind. Honestly, I don't think they want energy. Period."

Biden calls for net-zero emissions by the year 2050 in his climate policy, achieved by shifting away from fossil fuels but not completely banning them. Instead, Biden's policy would focus on developing carbon capture technology to reduce pollution and carbon outputs. Biden has called for no new fracking on federal lands, but that would not affect fracking already taking place or on private land.

The president also overstated what the memorandum would do. The Trump administration's memo only directed that government officials conduct an assessment of the "potential effects of efforts to ban or restrict" the use of "hydraulic fracturing and other innovative technologies for the use of domestic natural resources, including energy resources" within 70 days. 

-ABC News' Will Steakin and Justin Gomez

With nearly $300 million in total spending pouring in, the North Carolina Senate race has been the most expensive congressional race so far in 2020, followed by Iowa and South Carolina, according to data from the Center for Responsive Politics.

In the 10 most expensive Senate races this year, Democrats have been vastly outraising and outspending Republicans, especially where Democratic challengers are competing against Republican incumbents, the center's analysis of campaign spending records shows. Outside political groups not affiliated with the campaigns have also been driving up the spending.

Across the Senate battleground, North Carolina could possibly be the state that tilts control of the chamber -- reflected in $280 million in both campaign and outside money being poured into the state. The candidates have spent more than $64 million in the contest, with Democrat challenger Cal Cunningham raising and spending more than twice the amount of Republican Sen. Thom Tillis. Outside groups have also spent upward of $215 million supporting the two.

The contest between Republican Sen. Joni Ernst and Democratic challenger Theresa Greenfield in Iowa has also attracted far more spending from political interest groups than the candidates. Outside groups have funneled at least $170 million into the race, with more than $94 million going into unseating the incumbent senator and more than $74 million spent to fend off the challenger. The candidates' campaigns have spent about $64 million combined so far.

South Carolina has spent more than $209 million in a surprisingly competitive race for this cycle. The candidates have spent far more than outside groups in this race, with $164 million being spent by Democrat Jaime Harrison and GOP Sen. Lindsey Graham, compared to $45 million by outside groups. Harrison's campaign had raised $107 million and spent $104 million of that by mid-October, while Graham has raised $72 million and spent $60 million.

-ABC News' Kendall Karson and Soorin Kim

At the second of his four Pennsylvania rallies on Saturday, President Donald Trump railed over a recent Supreme Court ruling allowing absentee ballots in the state to be counted after Election Day in Pennsylvania and North Carolina.

 “I've had many disappointing opinions from the Supreme Court, I will tell you,” Trump said at the rally in Reading. "That was a terrible decision."

He also conflated the likely delay in election results due to the historic increase in mail-in ballots with voter fraud, of which there is very little evidence, and baselessly claimed votes counted after Election Day would be “when the cheating’s gonna take place."

"Do you know when the cheating’s gonna take place? From the third to whatever the date it is that they gave," he said, calling the deadline extension "disappointing."

"That was a very political decision, I have to say," he said.

-ABC News' Will Steakin and Elizabeth Thomas