Story highlights "The lives and well-being of millions of Americans are at stake," Lewis said in the letter obtained by CNN

Trump has branded Lewis, an icon from the civil rights movement, as "all talk"

Washington (CNN) John Lewis is working to channel the Democratic anger built from his recent fight with President-elect Donald Trump into an effort to save Obamacare.

In a letter to House Democrats obtained by CNN on Wednesday, Lewis, a Democratic congressman from Atlanta, said he was "deeply moved by your thoughtful words and sentiments."

Lewis is skipping the Inauguration, and his recent fight with Trump over whether he was a "legitimate" president spurred dozens of Democrats to boycott the ceremony on Friday.

Yet Lewis encouraged those Democrats attending to "demonstrate their commitment to the work ahead by showing their solidarity," on Obamacare, which Republicans are set to repeal.

"The lives and well-being of millions of Americans are at stake," Lewis said in the letter. "I hope you will use the next few days to reflect upon the role we must play within the 115th Congress to strengthen and protect this important legislative achievement."

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