A leading Democratic super PAC has promised it will tangle in court with President Donald Trump’s reelection campaign to keep airing television ads the Republican president is trying to keep off the airwaves.

Priorities USA Action chief Guy Cecil said Thursday that his group will intervene as a defendant in a lawsuit that Trump’s campaign filed in Wisconsin state court to block a local NBC affiliate from airing one of the super PAC’s ads that blasts the president’s response to the coronavirus pandemic.

“The Trump campaign is trying to railroad a TV station into censorship of ads critical of the president, and we will not let that stand,” Cecil said. “We stand by the facts in the ad and will defend it in court if necessary.”

The lawsuit, filed against WJFW-TV, an NBC affiliate in northern Wisconsin, sets up a notable battle between Trump’s financially flush reelection campaign and one of the biggest spending groups in Democratic politics. Priorities USA has spent much of Trump’s term researching voters’ views in key battleground states, including Wisconsin, that delivered Trump his Electoral College victory in 2016, and the PAC has committed to an extended television and digital advertising campaign to potential swing voters in those states.

The ad in question pieces together audio clips of the president downplaying the threat posed by the COVID-19 virus, while a chart that is splashed across the screen gradually begins to shoot upward as cases of the virus skyrocketed across the nation.