Stephen Colbert began Wednesday's Late Show monologue noting that polls are tight in the presidential race, then mentioned that Donald Trump is urging Hillary Clinton supporters to change their votes — which is apparently something you can do in some states. Colbert was having none of it. "I don't know what you learned as a kid, but no fair changies," he said. "No backsies. You vote, you're stuck with it. It's like a tattoo." Trump is also selling spots on his donor wall — though before you send Trump your $49, read Dana Milbank's story in The Washington Post of how Trump "stiffed" him. "That's right — Donald Trump is building a wall and making his donors pay for it," Colbert said.

Colbert then turned to Trump supporters, and one in particular. "Sometimes one bad apple makes all of the other apples seem racist," he said, cueing up that video of the guy at a Trump rally yelling "Jew-S-A!" "It is absolutely horrible to hear that sort of anti-Semitic language," he said. "Usually you just read it in Yahoo comments." But a newspaper tracked the man down, and he explained that he wasn't yelling "Jew-S-A" but rather trying to make the Mexicans in the crowd feel better about their accents and he was "just horsing around" when he said "the Jews run the country." "I'm going to call this the worst excuse of all time," Colbert said.

"So this election has now officially ruined everything," he said: "Horses, taco bowls, Billy Bush's career, and now — brace yourself — it's ruined yogurt." Because the founder of Chobani yogurt is helping migrants and refugees, people are proposing a boycott and posting vile and racist things on its social media pages. "And its no surprise that online trolls are in a race to the bottom, because that's where all the fruit is," Colbert said. He ended by noting that Glamour has named Bono as its first male woman of the year, because he gets it. Colbert rolled his eyes: "It's like the old saying: In front of every great woman stands a guy who really gets it." Watch below. Peter Weber

Two 2020 Democrats may have just scored — literally — the most crucial endorsement of the race: they've got the backing of Parks and Recreation's Leslie Knope.

This, at least, is according to Amy Poehler, who on Thursday speculated about which Democrats running for president might receive the support of her beloved sitcom character. The first person to come to mind was Sen. Amy Klobuchar (D-Minn.), who Poehler called a "Midwest candidate."

Poehler also agreed with the interviewer that Knope might support South Bend Mayor Pete Buttigieg, whose "underdog status" Poehler said her character would like, although neither of them could actually remember his name; Poehler seemed to think it was "Paul." Buttigieg had the best response, tweeting, "Wait till she realizes she's talking about the Indiana Parks and Recreation Association’s 2018 Elected Official of the Year..."

Weirdly, a name that didn't come up at all was former Vice President Joe Biden, even though Leslie Knope famously had an almost unhealthy obsession with him on the show. Biden even had a cameo in a scene where Leslie meets him and nearly passes out due to excitement. Maybe Poehler didn't count him since he's not officially in the race yet — or perhaps Leslie has discovered some horrifying secret about Biden's waffle opinions. Brendan Morrow

A nine-year-old girl who is a U.S. citizen says she was "scared" and "completely by myself" while being detained at the border for more than 30 hours.

Thelma Galaxia told NBC San Diego that her two children, 9-year-old Julia Isabel Amparo Medina and 14-year-old Oscar Amparo Medina, were on Monday being driven to school from Tijuana to San Diego by her friend, who told them to walk across the border after being worried that heavy traffic would make them late to school.

But the children were reportedly then detained by U.S. Customs and Border Protection and not reunited with their mother for more than 30 hours. Galaxia says officers told her daughter she didn't look like her passport picture, which was taken when she was younger. They reportedly accused her of lying about her identity and told her she would be released to her mother if she told them she was really her cousin.

Galaxia also says officers made her son sign a document identifying his sister as his cousin. "He was told that he would be taken to jail and they were going to charge him for human trafficking and sex trafficking," she said. The two were finally released when Galaxia called the Mexican consulate after being informed her children had been detained.

U.S. Customs and Border Protection officials told NBC San Diego that the young girl gave them "inconsistent info" and that they detained her so they could "perform due diligence in confirming her identity and citizenship," but they did not explain why this took more than a full day. Read more at NBC San Diego. Brendan Morrow

President Trump is closing out his workweek with — you guessed it — another attack on late Sen. John McCain (R-Ariz.).

Trump in an interview with Fox Business that aired Friday was asked by host Maria Bartiromo about his recent attacks on the Arizona senator, who died of brain cancer last year. "John McCain is dead," Bartiromo said. "Why are you doing this?" Trump used this as an opportunity to tear into McCain once again, saying he gave Christopher Steele's Russia dossier to the FBI for "very evil purposes" and that he "was horrible" for his vote against repealing the Affordable Care Act.

"I'm not a fan," Trump said of McCain.

Trump also insisted, though, that he's not the one bringing up the subject of McCain, saying, "I don't talk about it. People ask me the question. ... You people bring it up. I don't bring it up."

This is despite the fact that Trump originally began attacking McCain on Twitter, going after him in a tweet on Saturday and then again on Sunday, also retweeting a follower who said, "We hated McCain." This is what prompted questions from reporters. Trump also brought up McCain on his own during a speech on Wednesday, during which he went on an anti-McCain rant for several minutes.

Even if Trump were only talking about McCain when asked, though, he could always simply decline to answer these questions, a fact Trump acknowledged during this Friday interview. "I could say 'no comment,'" he said, "but that's not me." Watch Trump's latest exchange about McCain below. Brendan Morrow

Maverick is more than just Charlie's best friend — he's also his "seeing-eye" puppy.

Charlie and Maverick are golden retrievers, both owned by Adam and Chelsea Stipe of Mooresville, North Carolina. Charlie is almost 11 years old, and due to glaucoma, had his left eye removed in 2016 and his right in 2017. He still loves to play and go on walks but sometimes needs a little bit of help getting around. That's where Maverick comes in.

Maverick joined the Stipe family in January. Now four months old, Maverick walks next to Charlie, guiding him where he needs to go. Chelsea Stipe told NBC Philadelphia Maverick also noticed when Charlie would lose track of a toy, and would "pick it up and put it back in front of him to re-engage playtime." It took Charlie a bit of time to get used to Maverick, but now, they're inseparable. "They're both pretty crazy and special," Chelsea Stipe said. "They're definitely our entertainment." Catherine Garcia

At 94 years and 172 days old, Jimmy Carter is now the longest-living U.S. president.

Carter, the 39th president, was born on Oct. 1, 1924. When George H.W. Bush died in November, he was 94 years and 171 days old. Carter was also the first American president born in a hospital.

In office for one term, he has spent the last several decades dedicated to service, building houses with Habitat for Humanity and launching the nonpartisan and nonprofit Carter Center, which focuses on public policy. In 2002, he received the Nobel Prize. Carter announced in 2015 that he had cancer, which started in his liver and spread; he underwent surgery, and is now cancer-free.

Deanna Congileo, a representative of the Carter Center, told NBC News the organization is "grateful" for Carter's "long life of service that has benefited millions of the world's poorest people." Catherine Garcia

National Oceanic and Atmospheric Administration (NOAA) scientists on Thursday said "conditions are primed" for flooding in the Plains and Midwest that "could be worse than anything we have seen in recent years."

Mary Erikson, deputy director of NOAA's National Weather Service, said the "stage is set for record flooding now through May," because river levels are already high, soil moisture is above-normal, and there is substantial snowpack in the northern Plains, The Washington Post reports.

This week, there was deadly flooding in Nebraska and Missouri, and that could be just "a preview" of what might happen this spring. "This is potentially an unprecedented flood season," said Edward Clark, director of NOAA's National Weather Center. "It may become more dire in the coming weeks." The NOAA's spring flood outlook has 200 million Americans at risk, primarily those living near the upper, middle, and lower Mississippi River basins; the Great Lakes; as well as the eastern Missouri, lower Ohio, lower Cumberland, and Tennessee River basins. Catherine Garcia