Updated

The chief federal judge of Montana apologized Wednesday for sending a racist email about President Obama that appears to compare him to a dog, the Great Falls Tribune reported.

Chief U.S. District Judge Richard Cebull sent the email from his courthouse email address to seven recipients on Feb. 20, with the subject line, "A MOM'S MEMORY," according to the newspaper, which obtained a copy of it.

"Normally I don't send or forward a lot of these, but even by my standards it was a bit touching. I want all of my friends to feel what I felt when I read this. Hope it touches your heart like it did mine," the email reportedly began.

"A little boy said to his mother; 'Mommy, how come I'm black and you're white?'" the email joke reads. "His mother replied, 'Don't even go there Barack! From what I can remember about that party, you're lucky you don't bark!'"

Cebull was not immediately available for comment when contacted Thursday by FoxNews.com.

In an interview with the newspaper, Cebull admitted to sending the email and acknowledged that it was racist. But the judge told the Tribune that he doesn't consider himself a racist and said he sent it because he is "anti-Obama."

"It was not intended by me in any way to become public," Cebull told the newspaper. "I apologize to anybody who is offended by it, and I can obviously understand why people would be offended."

"The only reason I can explain it to you is I am not a fan of our president, but this goes beyond not being a fan," he reportedly said. "I didn’t send it as racist, although that’s what it is. I sent it out because it’s anti-Obama."

Cebull, who was appointed by President George W. Bush, has served as chief judge for the District of Montana since 2008.

In a statement released Thursday, Common Cause, a non-profit government watchdog group, called for Cebull's resignation over the "highly offensive racist email."

"If he has any respect for his office and for ideals of equality and human dignity on which our country was founded, Judge Cebull will step down today," said Bob Edgar, president and CEO of the group. "The message he has acknowledged circulating demonstrates a lack of judicial temperament that ought to disqualify him from further service.

"When Judge Cebull circulated this message, he expressed hope to recipients that it 'touches your heart like it did mine,'" Edgar said. "Now he wants us to believe he was motivated by his political disagreements with the President. In either case, in expressing such sentiments he has demonstrated his unfitness for the bench."

Click for more on this story from the Great Falls Tribune