(CNN) Republican Sen. Mitt Romney will not be invited to a major conservative conference following the Utah Republican's vote Friday in support of witnesses during the Senate's impeachment trial, the event's chairman said.

Matt Schlapp, chairman of the Conservative Political Action Conference, tweeted on Friday, "BREAKING: The 'extreme conservative' and Junior Senator from the great state of Utah, @SenatorRomney is formally NOT invited to #CPAC2020."

Romney and Sen. Susan Collins of Maine were the only two Republicans to break ranks and join the chamber's 47 Democrats in voting to allow subpoenas for witnesses and documents, a move that would have extended the trial. The pair's efforts failed, as their fellow potential Republican defectors, Sens. Lisa Murkowski of Alaska and Lamar Alexander of Tennessee, ultimately voted against witness testimony to seal the 51-49 total.

Schlapp's tweet appeared to reference when Romney, while running for president in 2012, infamously said he was "severely conservative" -- not "extremely conservative" -- at CPAC. President Donald Trump has spoken at the conference several times.

CNN reported Friday morning that Romney intended to vote in favor of witness testimony during the trial as expected, according to an aide. During a break in proceedings on Friday evening, Romney, Collins, Murkowski and Alexander were among a number of senators who met with Senate Majority Leader Mitch McConnell, a Kentucky Republican.

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