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Mr Kinzinger, whose popularity with his own party members tanked due to his service on the House Select Committee on the January 6 attack, decided not to run for re-election to his House seat. He and Rep Liz Cheney are the only two Republicans on the committee, and neither will be returning to Congress next year after she lost a primary challenge to a pro-Donald Trump challenger.
In his speech, Mr Kinzinger did not mince words about the direction his party has taken.
“Our leaders today belittle and in some cases justify attacks on the US Capitol as ‘legitimate political discourse.’ The once-great party of Lincoln, Roosevelt, and Reagan has turned its back on the ideals of liberty and self-governance,” Mr Kinzinger said. “Instead, it has embraced lies and deceit.”
Mr Kinzinger, a 44-year-old military veteran, was first elected to Congress in the Tea Party wave of 2010 and has served six terms since — winning re-election by comfortable margins. He supported many central tenants of the Republican platform over the last decade, including tax cuts that favoured the wealthy and the repeal of the Affordable Care Act.
He did not, however, support efforts led by former President Donald Trump to overturn the result of the 2020 presidential election and accepted Speaker Nancy Pelosi’s nomination to the committee investigating the attack. Since then, Mr Kinzinger has become one of the chamber’s most bipartisan members and a staunch critic of the Republican Party.
“The Republican Party used to believe in a big tent which welcomed the tired, the poor, the huddled masses yearning to breathe free,” Mr Kinzinger said during his speech. “Now, we shelter the ignorant, the racists who only stoke ignorance and hatred to those who are different than us.”
It is not clear what Mr Kinzinger, who has said that Mr Trump is “absolutely guilty” of a crime for his conduct on and around January 6, plans to do after leaving office in January. In additon to Mr Kinzinger and Ms Cheney, six of the eight other House Republicans who voted to impeach Mr Trump will not be returning to Congress next year.