Fiorina grew up in the Bay Area and became chief executive officer of Hewlett Packard there before plunging into politics with an unsuccessful run against Democratic Sen. Barbara Boxer in 2010. But this is no usual Republican presidential primary, and Fiorina's appearance won't quite be the return of a favorite daughter.
She's running on a ticket with Sen. Ted Cruz, who's mathematically eliminated from becoming the GOP presidential nominee unless the Republican National Convention is contested. Fiorina left California for Virginia shortly after losing her Senate race and didn't pay several California operatives for years, until she was running for president herself this winter.
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Even Fiorina's return was basically a toe-touch. She flew in after a day of stumping in must-win Indiana, gave a brief speech punctuated with digs at Trump then rushed out to fly back to Indiana. But she brought the crowd to its feet Saturday night after a series of zingers aimed at the front-runner, mocking his insistence the previous day that he essentially had the nomination sewn up.
"The 30-yard-line ain't a touchdown. The 20-yard-line ain't a touchdown. The 5-yard-line ain't a touchdown. It ain't a touchdown until it's a touchdown," Fiorina said, adding: "I'm sorry, you cannot just throw an 'R' on your jersey and say you believe what our party stands for."
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Fiorina's former home state is assuming outsized importance this primary season. Normally an afterthought in the presidential nominating contest, California's 172 delegates that are up for grabs on June 7 may decide whether Donald Trump becomes the party's nominee or if Cruz still has a shot to take the title on a second ballot at the Republican National Convention in July. Vice presidential selections rarely move votes in a general election, but Trump opponents are hopeful Fiorina can help Cruz in the Golden State's primary.
"She campaigned in this state very well, she won with these voters," said Rob Stutzman, a GOP operative helping with efforts to defeat Trump in the primary, referring to the base GOP voters who backed Fiorina in 2010. "She was a good Republican candidate here. She's the perfect surrogate for Cruz."
Fiorina won a bruising Republican primary in 2010, outflanking her opponents from the right to become the party's nominee to take on Boxer, a liberal who was viewed as vulnerable in the 2010 Republican wave. But Fiorina was trounced in the general election, losing by 1 million votes after being hammered for her stewardship of Hewlett Packard and role in outsourcing jobs overseas. Still, she won more votes in this overwhelmingly Democratic state than other Republican candidates for statewide office that year and displayed a hard-charging campaign style that endeared her to many Republicans.
State party chairman Jim Brulte said Fiorina was the first presidential candidate to respond to his invitation to appear at the state party convention that he issued to the entire presidential field in January, when she was still a contender for the top office. "That's probably because I sent it to her personal email account," he said.
Cruz spoke to the convention Saturday afternoon and highlighted his running mate, saying she'd be the first Californian on a national ticket since Reagan, although she lives in Virginia, home to many national political aspirants. Still, his references drew cheers and when he asked attendees if they knew why he picked Fiorina, one shouted, "Because she's good!"
Still, Fiorina disappointed some Republicans in California. GOP strategist Matt Rexroad was leaning toward Cruz but said the selection of Fiorina makes him question whether he'll support the Texan senator.
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Rexroad allowed that Fiorina will be popular among the party faithful at the convention. But that group is a tiny minority of Republicans who'll vote on June 7. "That isn't necessarily reflective of the electorate," he said.
Even the Fiorina faithful may not be won over to Cruz's side by her selection. Phyllis Stout, 75, from San Luis Obispo in Central California, was thrilled that Fiorina was speaking to the convention. "I loved her," she said of Fiorina's 2010 Senate bid. "She knew her stuff. She was a very intelligent lady."
But she's not going to vote for Cruz - there's just something about the Texas senator that Stout doesn't like. Instead, she's leaning toward Trump.
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The "protesters" in California were thugs and criminals. Many are professionals. They should be dealt with strongly by law enforcement!— Donald J. Trump (@realDonaldTrump) April 30, 2016
Protesters hold back a Republican supporter from getting into Hyatt where Trump will speak. pic.twitter.com/7FzH1cyNXv— Lyanne Melendez (@LyanneMelendez) April 29, 2016