(CNN) Mitt Romney signaled that he is moving toward a run for a US Senate seat from Utah, tweeting Thursday that he will make a formal announcement about his plans on February 15.

"Looking forward to making an announcement on February 15th about the Utah Senate race," he tweeted.

Looking forward to making an announcement on February 15th about the Utah Senate race. https://t.co/OLXWZWREEK — Mitt Romney (@MittRomney) February 1, 2018

Romney's intention to run for the seat of retiring Utah Sen. Orrin Hatch is an open secret in the state, but he's not expected to formally announce his bid until later this month, according to several sources close to the 2012 Republican presidential nominee.

While Romney has been quietly talking to potential aides in Utah, the tweet will allow him to hire a staff and make preparations more openly -- while also courting the conservative delegates who control the Utah GOP's nominating convention.

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