Story highlights Priorities is the Super PAC backing Democratic presidential nominee Hillary Clinton

Priorities also in October began attacking Republican incumbents in a pair of Senate races

(CNN) Hillary Clinton's flagship super PAC is raising roughly $1 million a day, according to new data provided by the super PAC, enough to finance an expensive and unprecedented independent assault on Donald Trump.

Priorities USA will report having collected about $18 million in the first 19 days of October, according to the group, an extraordinary fundraising clip that coincides with Clinton's strongest poll numbers to date . Largely thanks to about a dozen high-powered Democratic donors who can cut checks of unlimited size, Priorities has now raised over $175 million this cycle — easily the most of any outside group in the 2016 race.

The group said it had $15.1 million on hand as of October 19, meaning it poured nearly $25 million during that three-week period into its anti-Trump barrage, primarily on swing-state television. Trump super PACs have struggled to keep up with the fundraising or spending, and Trump forces have been significantly outgunned for the entire election.

The group has over $20 million reserved just on television for the final two weeks, according to advertising records.

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