Kirk Cousins and Russell Wilson were tied for the most games by a quarterback with 1+ passing touchdown in 2015, with 16 games.

what is the most 1 passing touchdown games by an nfl quarterback in a season in 2015
Interpreted as:
What is the most 1 or more passing touchdown games by an NFL quarterback in a season in 2015?
2015Cousins2015Wilson2015Fitzpatrick2015Palmer2015Rodgers2015Bortles2015Brady2015Manning2015Carr2015Ryan2015Brees2015Newton2015Stafford2015Bradford2015Cutler2015Rivers2015Smith2015Winston2015Tannehill2015Dalton2015Taylor2015Bridgewater2015Flacco161615151515151414141414141313131313121111109
NAMESEASONTMGPTDCMPATTPCTYDSAVGYDS/GTD%INTINT%SCKSCKYRATE
Kirk CousinsKirk Cousins2015WASWAS162937954369.84,1667.7260.45.3112.026186101.6
Russell WilsonRussell Wilson2015SEASEA163432948368.14,0248.3251.57.081.745265110.1
Ryan FitzpatrickRyan Fitzpatrick2015NYJNYJ153133155759.43,8596.9257.35.6152.7199487.8
Carson PalmerCarson Palmer2015ARIARI153531849764.04,4008.9293.37.0112.224147106.5
Aaron RodgersAaron Rodgers2015GBGB153133355060.53,7446.8249.65.681.54328793.6
Blake BortlesBlake Bortles2015JAXJAX153533857458.94,1897.3279.36.1162.84326490.3
Tom BradyTom Brady2015NENE153639060364.74,6367.7309.16.071.236211103.1
Eli ManningEli Manning2015NYGNYG143535455863.44,0737.3290.96.3142.52414195.8
Derek CarrDerek Carr2015OAKOAK143233053661.63,7577.0268.46.0132.43022592.4
Matt RyanMatt Ryan2015ATLATL142136153867.14,1137.6293.83.9132.42415292.8
Drew BreesDrew Brees2015NONO143240358369.14,6428.0331.65.5101.729225104.0
Cam NewtonCam Newton2015CARCAR143526343860.03,5128.0250.98.0102.330237102.7
Matthew StaffordMatthew Stafford2015DETDET143235252267.43,7777.2269.86.1132.54023598.5
Sam BradfordSam Bradford2015PHIPHI131932048665.83,5207.2270.83.9132.72316789.0
Jay CutlerJay Cutler2015CHICHI132127542065.53,1927.6245.55.092.12613896.1
Philip RiversPhilip Rivers2015SDSD132937655368.04,1497.5319.25.2101.828185100.0
Alex SmithAlex Smith2015KCKC132024037564.02,6567.1204.35.351.33315597.2
Jameis WinstonJameis Winston2015TBTB132224241358.63,2067.8246.65.3112.72315689.9
Ryan TannehillRyan Tannehill2015MIAMIA122426343560.53,0567.0254.75.592.12926991.5
Andy DaltonAndy Dalton2015CINCIN112523034367.12,9948.7272.27.351.516103112.6
Tyrod TaylorTyrod Taylor2015BUFBUF112019129864.12,4418.2221.96.751.729197105.0
Teddy BridgewaterTeddy Bridgewater2015MINMIN101419629566.42,3447.9234.44.731.032221102.1
Joe FlaccoJoe Flacco2015BALBAL91424838165.12,6747.0297.13.7102.61410786.9
Brian HoyerBrian Hoyer2015HOUHOU91920132561.82,3287.2258.75.861.81812195.3
Ben RoethlisbergerBen Roethlisberger2015PITPIT92124537265.93,2448.7360.45.6123.2128598.7
StatMuse has game-level data for passing touchdowns going back to the 1950 season.

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