Even as Joe Biden continues to lead Trump, he and Democrats stumble at every turn

The plane that was supposed to ferry reporters to a Joe Biden campaign stop in Pennsylvania broke down. A few minutes later, his running mate, Kamala Harris, had to pause her remarks at a much-anticipated Supreme Court confirmation hearing due to a poor connection.

Those hiccups came three days after House Democrats were so concerned by a medicated and coronavirus-infected Donald Trump's recent behaviour they crafted a bill to help Congress determine if a sitting president has become too impaired to serve – but did not write it so it would apply to Mr Trump before his term expires in January.

Those snafus come as national polls show Mr Biden maintaining a double-digit lead over Donald Trump with less than a month until Election Day. But they are merely three in a handful of miscues, mistakes and missed opportunities committed in recent days by top Democrats, including Mr Biden and Ms Harris.

On paper, things are looking strong for the Democratic ticket. That is, if they can avoid squandering what looks like a better-than-average shot at taking control of the White House and US Senate and living up to their reputation in Washington from finding ways to wrestle defeat from the jaws of victory.

Most national surveys have the former vice president up by at least 10 points, reflected in RealClearPolitics' average of a handful of polls, which puts him up by 10.6 percentage points. Two surveys released over the last couple of days show Mr Biden leading by more: an IBD/TIPP poll shows the former VP up by 11 points and a Washington Post/ABC News survey found a 12-point lead.

Swing state-specific surveys still give Mr Biden a lead in many, but like former Secretary of State Hillary Clinton in 2016, he is not putting any statistically significant distance between himself and Mr Trump in the campaign's closing weeks.

In short, Mr Biden has yet to prove himself as a political closer.

His and other Democrats' unforced errors and seeming refusal to grab what should be easy election-year messaging victories are hindering his and Ms Harris' efforts to slam the door on the president in crucial states like Florida, Pennsylvania, Michigan, Wisconsin, Arizona and North Carolina.

Polls show voters want Mr Biden and Ms Harris to state clearly if they would "pack" the Supreme Court if elected and should their party win a Senate majority. That is jargon for the idea of adding justices that agree with a party's ideology to the nine-judge high court; the US Constitution does not specify how many jurists must populate the court.

Yet, over the weekend, Mr Biden orchestrated Democrats' latest unforced error when asked by reporters if voters "deserve" to know his plans.  

"No, they don't deserve," Mr Biden replied, before catching himself and beginning to talk about Senate Republicans' decision to move towards a floor vote that would almost certainly put conservative federal Judge Amy Coney Barrett on the Supreme Court and give it a 6-3 conservative lean for decades to come.

On both that remark and Speaker Pelosi's decision to craft the presidential impairment legislation in a manner that would make it non-applicable to the very president she said makes it necessary, Democrats allowed Republicans to score messaging victories as they try to plant seeds of doubt about Mr Biden and Ms Harris while firing up their conservative base to get to the polls in what appears a turnout election.

About that legislation, the president tweeted minutes after the speaker announced it would not, if it somehow passed the GOP-run Senate, apply to him immediately: "Crazy Nancy Pelosi is looking at the 25th Amendment in order to replace Joe Biden with Kamala Harris. The Dems want that to happen fast because Sleepy Joe is out of it!!!"

Mr Trump's former ambassador to the UN and a potential 2024 Republican presidential candidate, former South Carolina Governor Nikki Haley called Mr Biden's "don't deserve" answer "amazing."

"No other candidate would ever get away from refusing to answer the question," she tweeted.

‘Not deserve’

The Trump campaign also pounced on the error.

"You said that voters 'don't deserve' to know if you'd go along with a scheme to pack the US Supreme Court. What other plans of yours do voters not deserve to know about?" the campaign asked in a blast email on Sunday.

The more Democrats stumble over their own political feet, the more Mr Trump can distract from issues that are among those on which he polls the worst with voters: the coronavirus and ongoing racial tensions -- just as he prepares to hit the campaign trail hard in the campaign's homestretch.

"The Economy is about ready to go through the roof. Stock Market ready to break ALL-TIME RECORD. 401k's incredible. New Jobs Record. Remember all of this when you VOTE. Sleepy Joe wants to quadruple your Taxes. Depression!!! Don't let it happen! #MAGA" he tweeted on Monday.

In another Monday tweet, he wrote: We will have Healthcare which is FAR BETTER than ObamaCare, at a FAR LOWER COST - BIG PREMIUM REDUCTION. PEOPLE WITH PRE EXISTING CONDITIONS WILL BE PROTECTED AT AN EVEN HIGHER LEVEL THAN NOW. HIGHLY UNPOPULAR AND UNFAIR INDIVIDUAL MANDATE ALREADY TERMINATED. YOU'RE WELCOME!"

The economy and healthcare are almost always voters' top two priorities when asked by pollsters to rank what matters most as they decide which candidate to support in a few weeks.