Gainer said people from the 1st district and in Washington, D.C. recently have encouraged him to run against McKinley.
"Quite honestly, it's something early in my political career I was always interested in doing," he said.
But the opportunity for a congressional campaign has only recently presented itself. Gainer is friends with former 1st District Rep. Alan Mollohan, a Democrat who served in that seat from 1983 to 2011.
Former state Sen. Mike Oliverio, D-Monongalia, defeated the longtime congressman in the 2010 primary election. McKinley then defeated Oliverio in that year's general election.
While Gainer said he is giving a 2014 congressional campaign a lot of thought, he emphasized he has not decided one way or another.
"I've made no decision and won't make any decision for a couple months," he said.
West Virginia Democratic Party Chairman Larry Puccio said he had heard Gainer was considering a run for Congress. He said no other Democrats have officially entered the 1st district race yet, but Gainer likely would make a good challenger for McKinley's seat.
"I definitely think an individual like Glen Gainer has so much respect from people around the state . . . he has so much credibility. I think he would be a strong candidate for that seat," he said.
Gainer's current job would not be in jeopardy if he were to run against McKinley and lose. His term as auditor will not end until 2017.