"I was an amateur boxer in my youth, and I brought that fighting spirit with me to Washington", said Hatch. But every good fighter knows when to hang up the gloves.
Romney, the former MA governor who now lives in Utah, has been eyeing a Senate run, but President Donald Trump had encouraged Hatch to seek re-election.
Hatch's decision not to pursue re-election is bound to shake up Utah state politics, and it is also likely to generate intrigue over the rumors that Mitt Romney is thinking about running to take his place. He is finishing up his seventh term in the upper chamber of Congress this year as the longest-serving Republican senator in history.
Romney has been an outspoken critic of President Donald Trump and the president has also lambasted him.
Hatchs decision comes just weeks after Trump signed a sweeping tax overhaul into law, a measure that the senator helped write as chairman of the Finance Committee.
At a rally for Alabama Senate candidate Roy Moore, Bannon called Romney, the GOP's 2012 presidential nominee, a draft dodger who "hid behind" his religion.
Amid earlier speculation about Hatch's plans, the Utah senator stepped up to defend Romney, a fellow Mormon.
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At least 23 people are injured in a fire that breaks out in a building in the Bronx, New York City, on January 2, 2018. All of the residents of the building were believed to have been evacuated as well.
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Committed to nuke dev in 2018: North Korea
The problem: The United States has adopted an untenable position by insisting on the elimination of North Korea's nuclear arsenal. He also said that "as long as there's no aggression against" North Korea, it does "not intend to use nuclear powers".
Hatch made his decision public Tuesday afternoon via a video announcement.
Hatch is now in his seventh term - first elected in 1976 - and is the Senate president pro tempore.
"Congratulations to Senator Orrin Hatch on an absolutely incredible career".
Other conservatives in the state have been trying to recruit another conservative challenger to contest Romney from the right, but no candidates have yet come forward.
Romney broke his silence on Facebook moments after Hatch's announcement, congratulating the retiring senator, listing his credentials and saying he and his wife wish them "all the best in their future endeavors".
That dynamic sparked a recent lobbying effort by the White House to encourage Hatch to seek another term in office. As the two senators talked over each other, Hatch said he was exhausted of Democrats' "bull crap".
Bloomberg News reported in October that Bannon was planning to play in nearly every Republican Senate primary contest, anyway, but a couple of the Breitbart News chief's would-be targets - Sen. One of his songs, "Unspoken", went platinum after appearing on "WOW Hits 2005", a compilation of Christian pop music.