American Bridge 21st Century is a Democratic Party super PAC founded by David Brock on November 23, 2010. Brock, a former conservative journalist turned liberal political consultant, founded the group to “set up what he hopes will become a permanent liberal counterweight over the airwaves to the Republican-leaning outside groups that spent so heavily” during the 2010 election cycle.
Brock is the leader and founder of several progressive political organizations, including Media Matters for America (MMFA) and judicial watchdog Citizens for Responsibility and Ethics in Washington (CREW).
American Bridge 21st Century Foundation, a federally registered 501(c)(4) social welfare organization, operates in tandem with the super PAC. In 2016, American Bridge 21st Century Foundation reported $6.8 million in revenues and $5.2 million in expenditures. 
From its inception, David Brock intended American Bridge to play a large role and sought the money to back up his plan.
In a New York Times article about the American Bridge’s founding, Brock boasted of his ability to raise substantial amounts of money from wealthy donors. Said Brock, “My donor base already constitutes the major individual players who have historically given hundreds of millions of dollars to these types of efforts.”
American Bridge’s early supporters included Rob McKay, chair of the Democracy Alliance, a fellow liberal organization, businessman Robert Dyson and television producer Marcia L. Carsey. Kathleen Kennedy Townsend, of Kennedy family fame and a former lieutenant governor in Maryland, served as the group’s first chair.
Purpose and Functions
American Bridge seeks to serve as something of a gaffe database, capturing political flubs and faux pas by Republican politicians on video. The group hired trackers to follow Republican candidates at the federal level and record their every word, handshake and everything in between. During the 2012 election cycle, American Bridge deployed trackers to 33 states. The group is crediting with finding the “legitimate rape” comments made by Missouri Republican U.S. Senate candidate Todd Akin, which led to a media maelstrom. Akin went on to lose the contest.
In the arms race of political tech and marketing, American Bridge hopes to amass one of the largest video and audio databases in existence.
During the 2016 election cycle, American Bridge enjoyed a $17 million budget and employed “ some eighty-plus staffers.”
Correct the Record
Also see Correct the Record (PAC)
In late 2013, Brock founded Correct the Record, an American Bridge spin off group, to defend statements uttered by Democratic candidates for president. Just about a year after Correct the Record’s launch, the left-of-center website the Nation described the site’s work “so far has meant defending [Hillary] Clinton constantly and consistently.” Between September and October 2016, Correct the Record accepted $250,000 in illegal contributions from Suffolk Cares Inc., a federally registered non-profit.
Following Clinton’s 2016 election loss, Correct the Record briefly attacked President Donald Trump’s nominees, but quietly ceased its operations. A few weeks later, Brock announced American Bridge would essentially take up Correct the Record’s function’s in the form of a “war room that will act as an aggressor and a watchdog for the Trump transition team.”
Brock pledged to perform deep investigate dives into Trump’s business interests, as well as the president’s philanthropic efforts and “privately” pass along American Bridge’s findings to media.
American Bridge also runs its “Rising Stars” program, which tracks Republican politicians that could one day seek higher office. The group’s trackers follow state- or local-level politicians and catalogue their public statements. As Mackler described it, “When somebody who ran for Congress in 2012 runs for president in 2028, we’re going to have an archive full of material.”
As of April 2017, American Bridge had deployed its trackers for Senate candidates in at least 10 states and the group planned to ramp up its efforts. The group plans to actively work U.S. Senate races in Montana, Indiana, Missouri, North Dakota, West Virginia, Florida, Ohio, Pennsylvania, Wisconsin and Virginia.
The group also planned tracking efforts in the 2017 New Jersey and Virginia gubernatorial races, including similar efforts in states like Wisconsin, Massachusetts and Illinois. There the group will target Republican Govs. Scott Walker, Charlie Baker and Bruce Rauner, respectively.
2018 Midterm Election
American Bridge and Brock have noted their intent to apply strong pressure against Republican candidates across the land. Brock said in the early planning stages of the 2018 midterm election cycle that “American Bridge will make running as a Republican candidate in the next four years painful. We will not only damage Trump, but also the candidates who enable and support him.”
In 2017 and 2018, American Bridge plans to track Republican U.S. Senate candidates Ohio’s Josh Mandel, Nevada’s Dean Heller and Arizona’s Jeff Flake. The group sees Arizona, where Flake is finishing his first term, as a significant pick-up opportunity for Democrats.
American Bridge has noted it plans to more actively participate in state legislative races after the 2018 midterm elections as the country approaches redistricting efforts, which can shift political power for a decade or more. The group says it will activate in, “state where a) Democrats are in the minority by a narrow margin in the state legislative chambers, b) redistricting is critical, and c) our progressive partners are most engaged.”
Brett Kavanaugh Confirmation
In July 2018, American Bridge announced its plan to work against the confirmation of President Trump’s Supreme Court nominee, Brett Kavanaugh, through personal vetting. Its research areas will cover FOIA requests, research through library collections and special collections, real property, corporate and nonprofit affiliations, national personal civil and criminal cases, comprehensive audio video search, and an anonymous tip line. 
Mike Stark Assault (2018)
Also see Mike Stark
On October 16, 2018, American Bridge reporter Mike Stark was arrested after he was accused of “grabbing and yanking” the arm of the female campaign manager for Nevada Republican gubernatorial nominee Adam Laxalt. According to his accuser, Stark attempted to enter a room in the East Las Vegas Community Center in order to film and question Laxalt when he “physically pushed his body on [her] multiple times” and twisted her arm aggressively. Stark was charged by the Las Vegas Police Department with battery and fired by American Bridge shortly thereafter. 
Criticism of Trump Administration
American Bridge 21st Century signed a letter condemning the immigration policy of the Trump Administration and urging American CEOs not to employ anyone involved with the policy. It accused these officials of being directly guilty for physical abuse, sexual assault, and even the death of illegal immigrant children. The letter was titled “An Open Letter to America’s CEOs” and was dated April 6, 2019. 
Jessica Mackler, a veteran Democratic campaign operative, serves as the group’s president. Heavyweight politico Brad Woodhouse held the post for 17 months before leaving to head up Correct the Record, a Brock spin-off. Mackler also presides over the American Bridge 21st Century Foundation.
Over the last decade, American Bridge 21st Century has reportedly received roughly $485,000 in union dues to “hold Republicans accountable.” 
2012: Receipts: $12,518,965. Disbursements: $11,227,734
2014: Receipts: $16,384,154. Disbursements: $17,316,603
2016: Receipts: $19,894,876. Disbursements: $19,724,727