On Friday, a photo with the words "Scott Walker Is Running For President" was tweeted from Walker's account.
A Twitter spokesman said Friday night that the tweet wasn't the Walker campaign's fault:
"We're looking into today's issue, and we've determined the Walker team was not at fault," the spokesman said in a statement.
Twitter did not provide further information on what exactly happened.
On Monday, Walker is expected to announce his candidacy, which will be the culmination of a lot of early pre-official campaigning for most of the year.
Since Iowa Freedom Summit this winter, he has aggressively campaigned in early presidential primary states this year and is considered a top Republican contender for the nomination.
The Wisconsin governor is best known for his battles with public unions. After he passed a budget that required public workers to contribute more money to their pension plans and limited collective bargaining in the public sector, unions protested for weeks, and ultimately helped force a recall election in 2013, which Walker won decisively. Because of the recall, the Republican has won three statewide elections in a blue state.
Early on, Walker has focused on his conservative record and pitched himself as a slightly more populist alternative to many of the other prospective candidates.
Katherine Miller is the politics editor for BuzzFeed News and is based in New York.
Contact Katherine Miller at firstname.lastname@example.org.
Got a confidential tip? Submit it here.