The Kennedy family has asked U.S. Sen. Cory Gardner (R-CO) to stop airing a political advertisement in which Gardner claims to have “finally fulfilled” a promise originally made by President John F. Kennedy.

“In 1962, John F. Kennedy made a promise in Colorado. It took 50 years to get it done, and it took Cory Gardner,” states the Gardner ad, apparently referring to an environmental law co-sponsored by Gardner and signed this year by Trump.

But Kerry Kennedy, John F. Kennedy’s niece, tweeted, “How dare you, Cory Gardner, misuse and abuse the memory of Uncle Jack in this grossly misleading advertisement. You have supported Trump’s decimation of the EPA and fueled global warming.”

The Colorado Democratic Party asked Gardner to “respect the wishes” of the Kennedys and remove the ad.

“Cory Gardner is no JFK,” said Colorado Democratic Party spokesperson Eli Rosen. “With just two days remaining in this campaign, Gardner needs to immediately respect the wishes of the Kennedy family and remove his disgraceful greenwashing ad that tarnishes JFK’s name. Stop misleading voters about your record and do the right thing.”

Gardner has been consistently trailing in polls against his Democratic opponent John Hickenlooper, who said in the pair’s last debate that just because Gardner embraced one environmental law it doesn’t mean he’s an environmentalist.

For his part, Gardner says the new law he’s been touting passed due to his tight connection with Trump. Gardner defends his relationship with the president by saying he works with him to get things done for Colorado.

Gardner’s critics counter by pointing out that Colorado’s junior senator has failed to criticize the president and votes with him about 90 percent of the time.

This post was updated with background information.