National Democrats hit the airwaves in Colorado on Wednesday with an ad countering an attack from national Republicans aimed at Democratic U.S. Senate candidate John Hickenlooper’s ethics violations.

The dueling ads land less than two weeks before ballots are due in the June 30 primary between Hickenlooper and former state House Speaker Andrew Romanoff, with the winner facing Republican U.S. Sen. Cory Gardner.

The new 30-second spot from the Democrats’ Senate Majority PAC labels an ad released Tuesday by the National Republican Senatorial Committee “politically motivated lies” a spokesman for the Democratic group called an attempt to distract from Gardner’s record.

The NRSC ad takes Hickenlooper to task over rulings by the state’s Independent Ethics Commission that the former governor violated a constitutional gift ban by accepting rides on a private plane and in a limousine during trips to promote the state. Hickenlooper, the ad blares, was the “first person ever” to be held in contempt by the commission for defying a subpoena to appear at a hearing earlier this month.

“The truth is 95 of the 97 Republican allegations were dismissed,” the Democrats’ ad says, citing the number of charges originally filed against Hickenlooper by a GOP-aligned group, though the vast majority were tossed because a statute of limitations had expired.

“The Denver Post calls Hickenlooper an ‘ethical public servant’ who made ‘an honest mistake,'” the ad continues, quoting from an editorial published the day before Hickenlooper was hit with a record-setting fine for the two ethics violations the commission found.

Then the ad explains why the SMP believes the Republicans are taking shots at Hickenlooper before the Democrats have chosen a nominee.

“Republicans know John Hickenlooper is the one who will beat Cory Gardner, who’s voted 98% of the time with Donald Trump. Those are the facts,” the ad says as a headline flashes on screen about a recent poll that showed Hickenlooper 18 points ahead of Gardner.

“Mitch McConnell and national Republicans see Cory Gardner’s double-digit hit in the polls and are sinking to new lows to buy this seat for Trump’s yes-man,” SMP spokesman Matt Corridoni said in a statement.

“We are setting the record straight about the facts and who’s behind them, while Gardner hides behind Mitch McConnell, President Trump and his record of siding with his party bosses over the needs of Colorado.”

A spokesman for the Colorado Republican Party dismissed the SMP ad as evidence the attacks on Hickenlooper are working.

“Chuck Schumer and Washington Democrats are so nervous about John Hickenlooper’s failing campaign that they are now investing more money into trying to prop him up,” Joe Jackson, state GOP communications director, told Colorado Politics. “Coloradans will see through this false ad and hold Hickenlooper accountable for these egregious ethics violations.”

Both ads are part of massive ad reservations the two groups placed this spring, when SMP set aside $5.2 million for ads in Colorado, and the NRSC reserved $6.2 million worth.