Pence will challenge his former boss Donald Trump, who is the clear Republican frontrunner so far.
Former US Vice President Mike Pence has formally submitted papers declaring his candidacy for next year's presidential election.
He's expected to announce his run at an event in Iowa on Wednesday, having filed the paperwork with the Electoral Commission on Monday.
It formally sets the 64-year-old on a collision course with his former boss Donald Trump, who is the clear Republican frontrunner so far.
Florida Governor Ron DeSantis is currently polling consistently in second. Still, Pence supporters see a lane for a reliable conservative who espouses many of the previous administration’s policies but without the constant tumult.
A staunch opponent of abortion rights, Pence supports a national ban on the procedure and has campaigned against transgender-affirming policies in schools.
He also has said the US should offer more support to Ukraine against Russian aggression while admonishing “Putin apologists” in the party unwilling to stand up to the Russian leader.
Pence, who describes himself as “a Christian, a conservative and a Republican, in that order,” has spent months laying the groundwork for an expected run, holding events in early-voting states like Iowa, South Carolina and New Hampshire, visiting churches, delivering policy speeches and courting donors.
Pence refused Trump's request to overturn the result of the 2020 presidential election, which resulted in him being targeted during the January 6th insurrection.