Brannan served as the Director of Communications and Legislative Affairs for Council member
Vincent J. Gentile, representing the
43rd district which includes
Bay Ridge,
Bath Beach,
Dyker Heights and portions of
Bensonhurst. by 682 votes. Brannan drew criticism from
The Indypendent newspaper during the campaign for accepting certain campaign contributions from real estate interests. Contributors to Brannan's campaign included $2,000 from Sal Raziano, a senior realtor of the real estate firm Casandra Properties and Anthony Constantinople (an amount under $1,000) of Constantinople & Vallone, a lobbying firm under investigation in 2017 for accusations of conflicts of interest and payroll discrepancies at its Sports & Arts program at a
Lower East Side public school. During the campaign, two of his opponent’s opponent’s employees and a third supporter of his opponent filed a complaint with the
New York City Campaign Finance Board in which they accused Brannan of neglecting to disclose campaign expenses when he failed to alert election regulators that Gentile’s campaign for Brooklyn DA paid the $2,000 rent for Brannan’s campaign office; Brannan’s campaign called the claims baseless. In the general election, Brannan won with 51% of the vote to the Republican candidate, John Quaglione's 47%. Brannan won by a slightly smaller margin in the
2021 election. In the 2024 general election for a redrawn 47th district, Brannan defeated his Republican colleague
Ari Kagan by 58 to 41 percent after they were drawn into the same district.
2025 Comptroller campaign Following the decision by New York City Comptroller
Brad Lander to challenge incumbent
Eric Adams in the 2025 Democratic primary for mayor, Brannan opened a campaign account for Comptroller. During the campaign, Brannan also sponsored some surveys for Public Policy Polling.
Politico declared
Mark Levine the winner of the Democratic primary for City Comptroller on June 24, 2025. ==Election history==