Story highlights Republicans have seized on the exchange

On Tuesday, Johnson suggested bias and potential corruption "at the highest levels of the FBI"

Washington (CNN) The chairman of the Senate Homeland Security Committee acknowledged Thursday that a reference made between two FBI employees of a "secret society" could have been said in jest as opposed to evidence of an anti-Donald Trump plot.

"It's a real possibility," Sen. Ron Johnson, R-Wisconsin, told CNN.

Republicans have seized on the exchange between FBI lawyer Lisa Page and FBI agent Peter Strzok, which was sent after the 2016 presidential election, as potential evidence of an anti-Trump bias at the agency. Strzok was a member of the team investigating Hillary Clinton's email server and, later, a member of Robert Mueller's special counsel team looking into Russia's attempted interference in the 2016 election.

"Are you even going to give out your calendars? Seems kind of depressing. Maybe it should just be the first meeting of the secret society," Page wrote to Strzok in a text message.

Sources familiar with the exchange told CNN later Thursday that the message contains a reference to a gag gift of Vladimir Putin-themed calendars that one of the employees purchased for those working on the early stage of the Russia investigation.

Read More