(CNN) — One of the Democratic Party’s largest super PACs on Thursday announced a $100 million campaign to reach about 2.5 million voters in four swing states — an early push by Democrats to challenge President Donald Trump in what will be a bruising and costly race for the White House in 2020.

The effort by Priorities USA starts now and focuses on expanding and mobilizing the pool of likely Democratic voters in Florida, Pennsylvania, Wisconsin and Michigan — states that backed Trump in 2016 after supporting his Democratic predecessor, President Barack Obama, four years earlier.

The campaign will rely heavily on digital advertising and media outreach to link Trump and his administration to Washington inaction on issues such as soaring health care costs, the group’s chairman Guy Cecil said Thursday.

About 80 staffers will work on the new effort, he said.

Priorities’ spending blitz comes as a slew of Democrats compete in earnest for the party’s nomination and Washington braces for completion of special counsel Robert Mueller’s Russia investigation. The President has repeatedly called the probe a “witch hunt.”

“We’re going to have a steady drumbeat that highlights and frames what matters during the chaos,” Cecil told reporters Thursday, as he outlined Priorities’ strategy and messaging. “So, while people are talking about Mueller, we’ll be talking about high health care prices,” he said. “When people are talking about tweets, we’ll be talking about wages.”

Asked to comment, Kayleigh McEnany, spokeswoman for the Trump campaign, responded: “We certainly welcome a debate on the President’s record. Thanks to President Trump, wages are growing at the fastest pace they have in ten years. … America is once again leading on the world stage, and President Trump has courageously tackled problems ignored for decades. … President Trump has and will continue to keep his focus on steadfastly winning for the American people.”

The four-state campaign will last until Democrats choose a nominee next year, Cecil said.

The group plans a separate push that will kick off later in the election calendar to target voters in another cluster of competitive states — Nevada, Arizona, North Carolina, New Hampshire and Georgia, a traditional Republican stronghold where Democrat Stacey Abrams mounted an attention-getting but failed bid for governor last year.

Priorities spent about $210 million in the 2016 presidential campaign to support Democrat Hillary Clinton. Guy said the group likely will spend as much in the 2020 fight, but it does not yet have a final budget for its presidential activity over the two-year election cycle.

The super PAC, which can raise and spend unlimited amounts to influence elections, was first established as a vehicle to support President Obama’s re-election in 2012. And its spending comes as a growing number of Democratic presidential candidates disavow big money in politics or say they don’t want super PACs working on their behalf.

Asked about those candidate denunciations, Cecil said Priorities has evolved from its roots as a super PAC aligned with a single presidential candidate to an organization working to “build a permanent digital infrastructure” for Democrats and expand voting rights through a nonprofit wing.

And he emphasized that the group won’t sit on the sidelines — no matter who wins the Democratic presidential nomination.

“Our focus is on three things: one, defeating Donald Trump, two, electing a Democratic majority to the United States Senate and on increasing turnout up and down in the ballot in all the states that we engage” Cecil said. “We intend to do that all the way through November of next year.”

The-CNN-Wire

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