Joe Biden's campaign has lashed out over "sustained and vitriolic" attacks on the 76-year-old Democrat's troubling senior moments (which even Democratic media operative Stephen Colbert called him out on last week).

"I don't know of anybody who has taken as sustained and vitriolic a negative pounding as Biden and who has come through it with the strength he has," a top Biden adviser told Politico. "So why isn’t the argument not that he's a ‘fragile front runner,’ but instead why is this guy so strong?"

Among the more recent campaign trail fumbles, Biden confused New Hampshire with Vermont, said the Kennedy and Martin Luther King Jr. assassinations happened in the late 1970s, claimed he was Vice President during the 2018 Parkland mass shooting, and so on.

And while not necessarily new to politicians, Biden has been lying about a war story while on the campaign trail.

On the stump, Biden often recounts a trip he made to Afghanistan while serving as vice president, frequently shifting the details of the trip, which the Post reported were demonstrably false. According to the Post, Biden visited the Middle Eastern country in 2008 when he was a senator, not vice president, and got nearly every other major detail of the trip wrong several times. Biden doubled-down on the story however, rejecting the claims by the Washington Post and standing by his statements regarding the fabricated trip. -The Federalist

That said, Biden remains the Democratic frontrunner despite his competitors catching up in most public opinion polls - and has even led President Trump in most hypothetical matchups.

The Washington Examiner, meanwhile, asked voters likely to participate in the Iowa Democratic caucuses about Biden - many of whom revealed misgivings over his age (at 78, he would be the oldest president to be inaugurated should he win), and whether he can go toe-to-toe with President Trump in the general election.

"I like him a lot. I’m concerned about his age," Democrat Cindy Schuman told the Examiner. "I’m just concerned about his energy."

Shcuman's 66-year-old husband Jon, a CPA, who said he is worried about Biden "as it relates to energy to do the job, not [to] beat Trump, because Trump’s just as old and probably in worse shape."

Apparently 73 is the new 76...

Still, many Biden supporters are happy to look the other way.

"Why do you keep asking about Biden’s gaffes when we have put up with three years of Trump’s absolute nonsense?" asked 80-year-old Democrat Virginia Peterson, who attended a Biden rally near Des Moines.

A Vanity Fair article, which was well-sourced within the Biden campaign, referred to news coverage as "Joe Biden outrage porn" and quoted former Fox News campaign correspondent Carl Cameron, now helming a liberal website, saying: "The idea that Joe Biden has loose lips is as old as Biden himself. “The problem for the press is that Trump says so much more stuff, all the time, and the ratio is just beyond description. He makes what we used to cover as gaffes look meaningless. So are we really going to have a gaffe-fest over Joe Biden?” Biden has acknowledged that his age is an issue. In a brief interview with reporters after a campaign rally in central Iowa during which Biden spoke extemporaneously for more than 60 minutes and then stuck around to take selfies with voters for another hour, he said voters will have to observe and decide for themselves. -Washington Examiner

"It’s a legitimate thing to [be] concerned about my age, just like it was legitimate to discern when I was 29 whether I had the judgment to be a United States senator. I think it’s totally legitimate," said Biden, adding "The only thing I can say is watch — watch. Check my energy level, determine whether I know what I’m talking about, make a judgment. That’s totally appropriate."

And according to Biden communications director Kate Bedingfield in an interview with MSNBC, "I think the press has to be more careful about applying an unfair standard to Joe Biden than they’re applying to other candidates," adding "He’s always speaking from his heart. And sure, that means sometimes he’s going to misstate a couple of things. But frankly, so does every other candidate."