If Romney Replaces Hatch, Senate Math Is All New

Utah's Orrin Hatch, the longest-serving Republican in the Senate, says he won't be running for re-election in 2018. The 83-year-old announced the move on Twitter. “Every good fighter knows when to hang up the gloves," he says in a video. "And for me, that time is soon approaching. That’s why after much prayer and discussion with family and friends, I’ve decided to retire at the end of this term." The move paves the way for Mitt Romney, a frequent critic of President Trump, to run for his seat. Details and developments:

• Unpopular at home: Hatch has been in the Senate for four decades and currently chairs the powerful Finance Committee, a post that allowed him to play a big role in the GOP's recent tax overhaul. But his clout doesn't seem to matter in Utah, where polls show that about 75% of residents wanted him to retire, reports the Salt Lake Tribune. (The newspaper itself issued a scathing editorial calling for him to do just that.)
• Trump unhappy: The president is "very sad" upon hearing the news, says spokeswoman Sarah Huckabee Sanders. The New York Times reports that the president, pleased with Hatch's work on the tax plan, had been encouraging him to run again. If nothing else, that would keep Romney—who has been vocal in his criticism of Trump—out of the Senate. (Still, Trump reportedly considered Romney for secretary of state.)

• Eyes on Mitt: Headlines about Hatch's decision are practically giving equal play to speculation about Romney. In a Facebook post, Romney praised Hatch for his long service but did not tip his hand on a possible run. Politico, among others, considers it "likely" that Romney will run. And the Atlantic notes that Hatch himself previously suggested that he'd step down if Romney would replace him.
• New Senate math: The seat is sure to stay in GOP hands, but conservative columnist Jennifer Rubin writes in the Washington Post that Romney, if he runs and wins, could well join Democrats on certain votes against the Trump agenda. He could be a swing vote of sorts, like Anthony Kennedy on the Supreme Court, she writes.
• Watch Bannon: Will Trump loyalist Steve Bannon, who wanted Hatch to run for re-election, back his own candidate in the race now? As the AP notes, Bannon went after Romney aggressively while campaigning for Roy Moore in Alabama. (Among other things, Bannon said Romney "hid behind" his religion to get out of military service.)