Republican Tom Marino, the incumbent representative for Pennsylvania's 12th congressional district, announced his resignation effective January 23, 2019. By state law, GovernorTom Wolf was required to call for a special election at least 60 days after the seat became vacant. Wolf set the election for May 21. Primary elections were not held in the race. Instead, nominees were chosen by each party. Republicans selected their nominee on March 2.
According to the Pennsylvania Democratic Party, Marc Friedenberg, the Democratic nominee for the district in 2018, was the only individual who submitted an application to be the nominee. Therefore, the convention was cancelled, and the party declared Friedenberg the nominee on February 12.
^Levy, Marc (November 6, 2018). "Democrats, 4 of them women, win House seats in Pennsylvania". Associated Press. Retrieved February 27, 2019.
^Oprysko, Caitlin; Motellaro, Zach (January 17, 2019). "Pennsylvania GOP Rep. Tom Marino to retire this month". Politico. Retrieved January 17, 2019.
^Tom Wolf [@GovernorTomWolf] (January 24, 2019). "Having heard the concerns of county officials, I am scheduling the special election to fill the remainder of Congressman Marino's term on May 21, 2019 to coincide with the primary election" (Tweet). Retrieved January 24, 2019 – via Twitter.
^Paez, Sarah. "Congressman Tom Marino resigns, leaving vacancy in Pa.'s 12th district | Centre Daily Times". Centredaily.com. Retrieved January 17, 2019.
^ abcdefghijklmnoKrawczeniuk, Borys (February 19, 2019). "Dozens eyeing Marino's vacant U.S. House seat". The Citizens' Voice. Retrieved February 19, 2019.
^ a b c d eKrawczeniuk, Borys (January 25, 2019). "List grows for those seeking Marino seat". citizensvoice.com. Retrieved March 7, 2019.
^Levy, Marc (March 2, 2019). "GOP state lawmaker becomes favorite in House race to succeed Marino". Center Daily Times. Associated Press. Retrieved March 7, 2019.
^"Former Commissioner Malcolm Derk is running for US Congress". WKOK. February 17, 2019. Retrieved February 18, 2019.
^Cole, John (February 12, 2019). "PA12: Stacy Garrity Announces Bid for GOP Primary". PoliticsPA. Retrieved February 13, 2019.
^Dandes, Rick. "Candidates step forward to replace Marino in U.S. Congress | Election 2019". dailyitem.com. Retrieved February 12, 2019.
^ ab"Candidates line up to replace U.S. Rep. Tom Marino". pennlive.com. Retrieved February 11, 2019.
^ ab"Election season is fast approaching. Who's running to represent Centre County?". centredaily. Retrieved February 14, 2019.
^Dandes, Rick. "Candidates step forward to replace Marino in U.S. Congress | Election 2019". dailyitem.com. Retrieved February 11, 2019.
^Barletta, Lou [@louforsenate] (February 1, 2019). "I am humbled by the number of you who have reached out to me. However, at this time, I am enjoying spending time with my family and preparing for the next chapter of my career. I look forward to helping elect the GOP candidate chosen by the conferees.(2/2)" (Tweet). Retrieved February 2, 2019 – via Twitter.
^ a b c d e f g"Marino Resignation Expected to Spark GOP Candidate Rush". National Journal. Retrieved January 18, 2019.
^ a b firstname.lastname@example.org, Rick Dandes rdandes@dailyitem com and Francis Scarcella. "Furious scramble to find replacement candidates in 12th District expected". The Daily Item. Retrieved January 18, 2019.
^Gizzi, John (January 20, 2019). "Just What GOP Doesn't Need, Another Special Election in Pa". Newsmax. Retrieved January 20, 2019.
^TaylorLightman (January 17, 2019). "Repub on the shortlist to replace Marino in #PA12: @senatorscavello @DougMclinko Rep. Fred Keller". @taylormlightman. Retrieved January 18, 2019.
^"Pennsylvania Democratic Party Announces Candidate For Special Election In The 12th Congressional District - Pennsylvania Democratic PartyPennsylvania Democratic Party". Padems.com. Retrieved February 12, 2019.
^Donald J. Trump. "Fred Keller of the Great State of Pennsylvania has been an outstanding State Rep. Now he is running as the Republican Nominee for Congress, and has my Complete and Total Endorsement. Strong on Crime, Second Amendment, Military, Vets, and Healthcare. He will do a fantastic job!". Twitter.
^ ab"Snyder County Commissioner Chair Kantz, Sheriff Zechman Recommend Keller". Fred Keller for Congress. February 21, 2019.
^ ab"Union Co. Chair Boop, Snyder Co. Vice Chairman Knepp Praise Fred Keller". Fred Keller for Congress. February 24, 2019.
^"ACU Endorses Fred Keller". American Conservative Union.
^Eyewitness News (May 2, 2019). "U.S. Chamber of Commerce Endorses Keller". PAHomePage.com.
^ ab"Leading Pro-Life Groups Endorse Fred Keller for Congress". Fred Keller for Congress. April 15, 2019.
^"NFIB Endorses Fred Keller in PA-12 Special Election". NFIB. April 4, 2019.
^"NRA-PVF Endorses Fred Keller for U.S. House". NFIB. April 8, 2019.
^"U.S. Chamber Endorses Fred Keller". Fred Keller for Congress. May 2, 2019.
^Fred Keller. "Proud to be endorsed by the Fraternal Order of Police Bald Eagle Lodge 51 in Centre County. Our law enforcement make sacrifices every day to keep us safe. I'll always have their backs. #PA12 #May21". Twitter.
^Hirsch, Jack (April 28, 2019). "Senator Bob Casey, other Pennsylvania Democratic candidates rally at Penn State". Daily Collegian. Retrieved April 28, 2019.
^"Endorsements". Marc Friedenberg For Congress. March 27, 2019.
^"I'm proud to be endorsed by Secretary Reich! The best way to improve our economy is by strengthening the middle class and creating more protections for working families, not with tax cuts to the ultra-rich, that take away our hard-earned benefits.https://www.youtube.com/watch?v=51MJjaHtv6M … #PA12". @MarcForPA. May 17, 2019. Retrieved May 17, 2019. External link in |title= (help)
^"Lieutenant Governor John Fetterman Endorses Marc Friedenberg for PA-12". Marc Friedenberg for Congress. April 16, 2019.