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Fiorina said that she didn't vote for herself last week during the Virginia primary last Tuesday on Super Tuesday, despite appearing on the ballot, but instead chose Cruz.
"I checked the box for Ted Cruz and I am here to tell you why," Fiorina said today.
“He has fought for our religious liberty,” she said. “He is a leader and reformer.”
Cruz "has won over and over and over,” she said, citing several primary and caucus victories so far. “He has won.”
"My fellow conservatives ... you have a very important job on Tuesday and I say to you it is time to take our party back," Fiorina said, referring to the upcoming Republican primaries in Ohio, Florida and Illinois among others next Tuesday. "It is time to take our government back. It is time to take our country back and so it is time now to unite behind the one man who can beat Donald Trump, who can beat Hillary Clinton."
"It is time to unite behind Ted Cruz," Fiorina said.
Cruz touted the endorsement as the Republican party coming together.
"It's easy to talk about the party coming together. We're seeing manifestations of this," Cruz said. He also referred to Fiorina, the former CEO of Hewlett-Packard, as a "serious thinker" and spoke of her business pedigree and knowledge of foreign policy.
Fiorina is the second former 2016 contender to endorse him after Rick Perry previously endorsed him in January.
Her endorsement comes at a time when other prominent Republicans are hinting that Cruz might be the one man to have the best shot of beating Trump. Sen. Lindsey Graham suggested it might be time to rally around Cruz. Cruz has also acknowledged exchanging calls and emails with Mitt Romney but Romney has not done robocalls for him as he has for other GOP contenders John Kasich and Marco Rubio.
Fiorina dropped out of the presidential race in early February after a disappointing seventh place finish in the New Hampshire primary.
The endorsement comes the day after Donald Trump chalked up major victories in Michigan and Mississippi and just a week before crucial contests for Rubio and Kasich in their home states next Tuesday.