Letters signed by 50 U.S. senators urging the league to change the Washington Redskins name were sent on Thursday to NFL commissioner Roger Goodell.

The senators draw a parallel between the NBA's no-tolerance policy regarding the racist comments made by Los Angeles Clippers owner Donald Sterling and asks the NFL to act similarly.

Redskins owner Daniel Snyder has been steadfast in his stance that he won't change his team's name. AP Photo/Manuel Balce Ceneta

"Today, we urge you and the National Football League to send the same clear message as the NBA did: that racism and bigotry have no place in professional sports," the senators write. "It's time for the NFL to endorse a name change for the Washington, D.C. football team.

"The despicable comments made by Mr. Sterling have opened up a national conversation about race relations. We believe this conversation is an opportunity for the NFL to take action to remove the racial slur from the name of one of its marquee franchises."

Redskins owner Daniel Snyder has opposed the name change, and his team has launched its own public relations campaign issuing comments by Native Americans that continue to support the name.

The NFL has stood behind Snyder and issued its own response Thursday to the news of the senators' letter.

"We have not received the letter, but the NFL has long demonstrated a commitment to progressive leadership on issues of diversity and inclusion, both on and off the field," NFL spokesman Brian McCarthy said in a statement. "The intent of the team's name has always been to present a strong, positive and respectful image. The team name is not used by the team or the NFL in any other context, though we respect those that view it differently."

The Oneida Indian Nation, a tribe located in upstate New York that has been pushing for the name change through a national "Change the Mascot" campaign, applauded the senators' formal action while continuing to stay on its message.

"Washington team owner Dan Snyder and NFL commissioner Roger Goodell have claimed that using the R-word epithet somehow honors native peoples, but it is quite the opposite," Oneida Nation CEO Ray Halbritter said in a statement. "The R-word is a dictionary defined racial slur."

Halbritter said that the Redskins name is not a term of honor but "a malicious insult."

Jackie Pata, the executive director of the National Congress of American Indians, also weighed in Thursday.

"The NFL is a global brand," Pata said in a statement released through Oneida. "But it wants to contribute to the positive image of the United States across the world rather than callously promoting discrimination against Native Americans, then it must stop promoting this slur and finally change the name."

One letter to the NFL was signed by 49 senators (only Democrats) and was not signed by Tim Kaine or Mark Warner, the two Democratic senators from Virginia.

Senator Bill Nelson (D-Florida) sent a separate letter to Goodell calling for the Redskins to change their name.