

Hillary Clinton, accompanied by Sen. Elizabeth Warren (D-Mass.), meets voters during a rally at Saint Anselm College in Manchester, N.H., on Monday. (Melina Mara/The Washington Post)

The top super PAC flanking Democratic presidential nominee Hillary Clinton has raised more money than any super PAC in history, scooping up nearly $175 million to finance its efforts, the group announced Tuesday.

Of that, more than $18 million poured in during the first 19 days of October, Priorities USA Action officials said.

That makes Priorities the most financially successful super PAC since a federal appellate court sanctioned the creation of such groups in 2010 in the case SpeechNow.org v. Federal Election Commission. Its total haul surpasses the amounts raised by Restore Our Future, a super PAC that backed 2012 GOP presidential nominee Mitt Romney ($153.7 million); Right to Rise USA, a super PAC that boosted former Florida governor Jeb Bush this year ($118.7 million); and the GOP super PAC behemoth American Crossroads in 2012 ($117.3 million).

GOP nominee Donald Trump, who denounced super PACs during the primaries, accepted their support in the general election. But the half a dozen groups that emerged to back him jockeyed over primacy and failed to meet their fundraising goals, together bringing in just $56 million through Sept. 30.

[How mega-donors helped raise $1 billion for Hillary Clinton]

Priorities' fundraising prowess, first reported by CNN, underscores how Clinton fully embraced super PACs, determined not to let Bush and other Republicans beat her in the money race. Hacked emails posted by WikiLeaks show how top Clinton officials, including campaign chairman John Podesta, recruited the support of wealthy donors for both the campaign committee and the super PAC.

The close cooperation between Priorities and Clinton's campaign was a drastically different approach than the one taken by then-candidate Barack Obama, who opposed outside spending on his behalf in 2008 and then reluctantly accepted the work of Priorities to bolster his reelection efforts in 2012, when the group raised nearly $79 million.

This cycle, one lone donor provided 12 percent of Priorities's funding: Hedge fund manager S. Donald Sussman told The Washington Post that he has given a total of $21 million to the super PAC. Sussman said he is hoping that Clinton and other Democrats overhaul the current campaign finance system that permits such large donations.

Priorities headed into the final three weeks of the 2016 campaign with $15.2 million in the bank, and has more than $15 million in television ad buys reserved for the final two weeks. As Clinton has widened her lead over Trump in the polls, the super PAC has begun directing some of its arsenal at vulnerable Republican Senate candidates Kelly Ayotte in New Hampshire and Patrick J. Toomey of Pennsylvania.