[5] After graduating from Shikellamy High School in 1984,[3] Keller got a job at Conestoga Wood Specialties, a factory that makes cabinets and other wooden kitchen products, in Beavertown, Pennsylvania.

[9] Following Tom Marino's resignation from the United States House of Representatives in January 2019, Keller declared his candidacy in the 2019 Pennsylvania's 12th congressional district special election.

[11] Keller won the general election on May 21, defeating previous 2018 Democratic nominee Marc Friedenberg, and resigned from his state House seat on May 22.

[15] In December 2020, Keller was one of 126 Republican members of the House of Representatives who signed an amicus brief in support of Texas v. Pennsylvania, a lawsuit filed at the United States Supreme Court contesting the results of the 2020 presidential election, in which Joe Biden prevailed[16] over incumbent Donald Trump.

The Supreme Court declined to hear the case on the basis that Texas lacked standing under Article III of the Constitution to challenge the results of the election held by another state.

[34] WITF refers to him as "Fred Keller, who voted against certifying Pennsylvania's election results for President Biden despite no evidence to support election-fraud claims.