Donald Trump’s presidential campaign says the Republican candidate will have a “major announcement and a very special guest in attendance” at a rally planned for Tuesday in Iowa.

“You will not want to miss this rally!” says Ryan Keller, the Iowa Deputy State Director for the campaign.

An online invitation posted by Keller says the rally is scheduled for 5 p.m. CST in Ames.

Trump told a crowd in New Hampshire that the announcement is an endorsement, but didn’t elaborate.

“We’re getting a big endorsement on Tuesday,” Trump said, according to the Washington Examiner. “It’s going to be a lot of fun.”

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