Priorities USA, the largest Democratic super PAC, announced on Thursday it will spend $100 million in four of the top swing states as part of an initial investment to try and defeat President Donald Trump.

Guy Cecil, the super PAC's chairman, held a briefing with reporters earlier in the morning, where he argued polling shows Democrats have "opportunity to expand the electorate to the largest, if not certainly the largest in a generation." In order to do that, the Democratic party shouldn't waste time and must start building an apparatus, he said. The group's initial investment will be in Florida, Michigan, Wisconsin and Pennsylvania, according to NBC News.

Liberal billionaire George Soros donated at least $9.5 million during the 2016 election cycle and $5 million to the group during the 2018 election cycle, making him one of its biggest donors. They also received millions of dollars from the House Majority PAC, which accepts money from corporations and PACs.

"We are going to have a long, year-and-a-half long, sustained conversation with these 2, 2.5 million voters in these four states," Cecil said.

The four states represent 75 Electoral College votes and were critical in helping Trump defeat Hillary Clinton in 2016. A large majority of the $100 million investment will be spent on digital ads and infrastructure in the states, NBC News reported.

Cecil walked reporters through a detailed theory of the case—including how Priorities views the universe of potential Democratic persuasion and turnout targets, as well as the messages it believes is best suited to win over those voters. He specifically called out the 16 percent of registered voters who did not vote for Democrat Hillary Clinton in 2016 that say they are open to supporting a Democrat in 2020. Of those, 51 percent did not vote in 2016, 20 percent voted for Trump because they opposed Clinton, 17 percent voted for a third party candidate and 12 percent voted for Trump because they supported him. Like other Democratic groups that have done postmortems after the 2016 race, Priorities wants to prioritize issues like health care and wages over the more general concerns Democrats have about Trump's tweets and temperament. The group's polling has found that Democrats have the biggest advantages when message on those issues, and less of an advantage when trying to message directly on Trump's tone or rhetoric.

"Our job is to refocus as much of the conversation on economic issues—not on tweets or temperament or personality, but on how this administration affects them," Cecil said. "While people are talking about Mueller, we will be talking about high health care prices…When people are talking about Trump’s temperament, well be talking about how Trump's temperament relates to the rising cost of pharmaceuticals."

Looking ahead to the general election, the group has "developed a more permanent infrastructure for the left that isn't focused on one election," Cecil said. They will attack Trump "all the way through November" regardless of the eventual Democratic nominee's position on super PACs, he added.

Several of the Democratic candidates have already formally announced plans to reject donations from corporate PACs, including Julian Castro and several senators: Kamala Harris (D., Calif.), Bernie Sanders (I., Vt.), Kirsten Gillibrand (D., N.Y.), and Elizabeth Warren (D., Mass.).