The endorsement comes despite Cruz's calls on Tuesday for law enforcement to “patrol and secure Muslim neighborhoods” in the wake of terrorist attacks in Belgium. When Trump called for a database to track American Muslims after terrorist attacks in Paris last November, Bush called the front-runner's comments "abhorrent."
As a candidate Bush raised tens of millions of dollars from a vast national network of supporters who helped bankroll his campaign and an allied super PAC. But most Bush donors have stayed out of the fray since the governor dropped out of the presidential race last month.
Bush insisted that governors, not senators, are better equipped to serve as president because state executives regularly make tough decisions while lawmakers just propose legislation. There appeared to be no deep personal animosity between Bush and Cruz despite stylistic and policy differences and they rarely clashed on a debate stage or had cross words for each other on the campaign trail.
The former governor has privately expressed admiration to friends and associates for the senator's commitment to his conservative beliefs despite his frequent clashes with Republican colleagues. In recent weeks, those associates said Bush has determined that Cruz is now the most electable alternative to Trump, an opponent with whom he bitterly clashed.
A formal announcement came early Wednesday after Bush and Cruz aides shared news of the endorsement in advance with The Washington Post and other outlets.
"Ted is a consistent, principled conservative who has demonstrated the ability to appeal to voters and win primary contests," Bush said in a prepared statement. "Washington is broken, and the only way Republicans can hope to win back the White House and put our nation on a better path is to support a nominee who can articulate how conservative policies will help people rise up and reach their full potential."
"For the sake of our party and country, we must move to overcome the divisiveness and vulgarity Donald Trump has brought into the political arena, or we will certainly lose our chance to defeat the Democratic nominee and reverse President Obama’s failed policies," Bush added. "To win, Republicans need to make this election about proposing solutions to the many challenges we face, and I believe that we should vote for Ted as he will do just that."
Cruz called Bush "an extraordinary governor of Florida" whose job creation and education record "left a lasting legacy" for Floridians. The endorsement, Cruz said, "is further evidence that Republicans are continuing to unite behind our campaign to nominate a proven conservative to defeat Hillary Clinton in November, take back the White House, and ensure a freer and more prosperous America for future generations."
Early signs of Bush's likely support came this month when he met privately with Cruz in Miami ahead of a GOP presidential debate there. The meeting came as Neil Bush, the governor's younger brother, joined Cruz's national finance team. Neil Bush lives in Houston and runs in the same social circles as the senator and his wife, Heidi. Other former top Bush bundlers, including C. Boyden Gray and Reginald J. Brown, also signed up with Cruz this month.
Then there's Sen. Lindsey O. Graham (R-S.C.) -- one of Cruz's most frequent foils on the Senate floor -- who announced plans to hold a fundraiser for his colleague and former presidential rival. Graham and Bush developed a close bond during the final weeks of Bush's presidential campaign as the pair campaigned together across South Carolina.
And don't forget George P. Bush.
The 39-year old Texas land commissioner is now considered the Bush family's next best hope to reclaim the White House, but he cannot expect to easily advance in Texas state politics without Cruz's support.
In 2010, Jeb Bush's sons, George P. Bush and Jeb Bush Jr., endorsed Cruz's long-shot Senate bid as part of their work for Maverick PAC. The group was founded by younger members of George W. Bush's administration with the intent of endorsing younger GOP congressional candidates. Jeb Bush Jr. remains active with the group, while Cruz, 45, has aged out and George P. Bush had to step down due to his statewide political position.
Meanwhile, Jeb Bush has stayed out of the public spotlight since ending his campaign last month. Friends say he now spends time at the stately Biltmore Hotel near his home, working out of his personal office suite, swimming laps in the pool or playing rounds of golf.
But he may re-emerge on the campaign trail soon, because aides said that the former governor plans to "actively support" Cruz.