Rep. Tom McClintock (R-Calif.) came out swinging on Tuesday against the impeachment of Secretary of Homeland Security Alejandro Mayorkas.

Why it matters: McClintock's position means Republicans are down another vote as they try to impeach Mayorkas with a razor-thin House majority. Rep. Ken Buck (R-Colo.) is also opposed, with several other Republicans undecided.

• The Democrat-controlled Senate is highly unlikely to convict Mayorkas even if the impeachment does proceed.

What he’s saying: McClintock wrote in a 10-page memo that the articles of impeachment drafted by the Homeland Security Committee “fail to identify an impeachable crime that Mayorkas has committed.”

• "In effect, they stretch and distort the Constitution in order to hold the administration accountable for stretching and distorting the law," he added.

McClintock also argued that it is "delusional to believe the Senate will vote to remove Mayorkas on the grounds laid out" in the articles, saying it will "at best be a party-line vote."

• "More likely, it will be a bi-partisan repudiation of a misuse of power," he said — a reference to Senate Republicans who have criticized the House's case for impeachment.

State of play: The House is set to vote Tuesday on two articles of impeachment accusing Mayorkas of "willful and systematic refusal to comply with the law" and "breach of public trust."

• The case centers around allegations that Mayorkas declined to enforce laws around the detention and deportation of migrants along the U.S-Mexico border.