Newt (the politician) mourns Knut (the polar bear)

While his Democratic Party detractors have long accused Newt Gingrich of not having a heart, the Republican heavyweight showed he has a soft spot for critters in mourning the death of his phonetic namesake, Knut.

Knut, a 4-year-old polar bear and star attraction at the Berlin Zoo in Germany, died suddenly and unexpectedly at the zoo on Saturday — and Gingrich quickly used social media to express his sorrow.

“Sad news! Just learned that Knut the polar bear died suddenly at 4 — (wife) Callista and I visited him in Berlin when he was five months old. He was cute,” Gingrich wrote on Twitter.

And on his Facebook page, Gingrich wrote, “Callista and I were sorry to learn of the unexpected passing of Knut this weekend.”

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Indeed, Mr. and Mrs. Gingrich bonded with Knut during their German holiday in 2007, and Newt invoked Knut’s name numerous times later that year in promoting his go-green book, “A Contract with the Earth.”

Knut made headlines when, after he was rejected by his mother at birth, he was raised by zookeepers in Berlin instead. Along the way, he became an environmental cause celebre and a major tourist attraction; attendance at the Berlin Zoo roughly doubled after Knut made his official debut.

Knut got enough media attention to turn a politician green with envy — appearing with Leonardo DiCaprio on the cover of Vanity Fair magazine, becoming the subject of a film and spawning his own merchandising industry.

Related: Knut, Berlin’s beloved polar bear, dies in his compound

Death by fame?
But the death of the seemingly healthy bear Saturday was bewildering. Some 600 zoogoers were watching Knut’s doings when he suddenly started shaking and walking in circles before collapsing into his zoo compound pool.

Zoo officials said preliminary findings in an autopsy performed Monday showed previously undiagnosed brain damage. But animal rights activists pointed to Knut’s celebrity lifestyle as his undoing.

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Activists contended Knut’s fame made him psychologically unbalanced and overly dependent on attention, and he was no longer able to socialize with other bears, reports London’s Daily Mail. Crowds watching Knut at the Berlin Zoo often reported him weaving to and fro and standing on his hind legs, trying to mimic the motions of visitors taking pictures of him. 

On Tuesday, Gingrich, the former U.S. Speaker of the House and expected 2012 presidential candidate, showed his affection for Knut on his Facebook page, displaying a photo of a beaming Newt kneeling next to the bear, then still a cub, at the zoo during his 2007 visit.

“I love that scruffy, white-haired beast — and the polar bear, too!” one waggish Facebook poster commented under the photo.

The Associated Press contributed reporting to this story.