Ted Cruz says he will vote for Donald Trump

Ted Cruz announced Friday he will vote for Donald Trump, a dramatic about-face for the Texas senator who previously called the New York businessman a "pathological liar" and "utterly amoral."

Cruz was facing intensifying political pressure to back his party's presidential nominee after refusing to do so at the Republican National Convention this summer.

Cruz said he will vote for Trump in November, but he stopped short of an official endorsement in a statement posted Friday onFacebook.The distinction may matter little to voters, but helps Cruzsave face among his loyal supporters still unwilling to forgive Trump's attacks on the Texas senator's wife and father during their ugly, and often intensely personal primary campaign.

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Cruz noted that he was booed by Trump supporters at the convention for encouraging Republicans to "vote your conscience."

"After many months of careful consideration, of prayer and searching my own conscience, I have decided that on Election Day, I will vote for the Republican nominee, Donald Trump," Cruz wrote.

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Trump accepted Cruz's support, describing it as an "endorsement" in a statement. That's even after Trump claimed he didn't want Cruz's endorsement immediately after the convention chaos.

"I am greatly honoured by the endorsement of Senator Cruz," Trump said Friday. "We have fought the battle and he was a tough and brilliant opponent. I look forward to working with him for many years to come in order to make America great again."

Cruz finished second to Trump in a bitter primary battle and balked at previous promises to endorse the eventual Republican presidential nominee. He said Trump made things too personal when he called him "Lyin' Ted," insulted Cruz's wife Heidi and repeated discredited accusations linking Cruz's Cuba-born father to the John F. Kennedy assassination.

"This man is a pathological liar. He doesn't know the difference between truth and lies. He lies practically every word that comes out of his mouth," Cruz said of Trump in May, hours before ending his presidential campaign.

"Donald will betray his supporters on every issue," the Texas senator added, while calling Trump "utterly amoral," "a narcissist," "a bully," and "a serial philanderer," among other things.

Cruz saysClinton is'wholly unacceptable'

Cruz cited two reasons for his shift.

"First, last year, I promised to support the Republican nominee. And I intend to keep my word," he wrote. "Second, even though I have had areas of significant disagreement with our nominee, by any measure Hillary Clinton is wholly unacceptable that's why I have always been #NeverHillary."

Since the convention speech, polls have suggested that Cruz's popularity was slipping nationally and in Texas where he could face a primary challenger for re-election in 2018.

Trump himself even praised the idea of former Texas Gov. Rick Perry running against Cruz in 2018. Trump said Perry would do well, though Trump said he didn't know whether Perry would run.

Cruz also faced intensifying political pressure from other quarters.

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His base was overwhelmingly supportive initially, but the mood shifted recently. The vast majority of calls coming into Cruz's office had turned increasingly negative in recent weeks with many voters urging him to support Trump to prevent a Clinton victory, according to Republicans familiar with the situation. The Republicans spoke on the condition of anonymity because these were internal discussions.

At the same time, the large staff that worked on Cruz's presidential bid pushed him not to endorse. Most refused to accept jobs with the Trump campaign when offered following Cruz's departure from the primary campaign this spring. And as recently as this week, some warned they would not work for Cruz again if he officially endorsed Trump.

Trump's naming of Cruz ally, Utah SenatorMike Lee, in his updated list of potential Supreme Court picks announced Friday helped ease tensions between the two camps. Trump also backed Cruz's position in a congressional squabble over internet regulation.

Yet bad blood remains.

The decision to announce his intention to vote for Trump, rather than endorse him outright, was seen as a compromise even if voters see little distinction between the two. Other Republican leaders in difficult political situations, notably New Hampshire Sen. Kelly Ayotte, have taken similar positions.

"Hillary Clinton is manifestly unfit to be president, and her policies would harm millions of Americans," Cruz wrote Friday. "And Donald Trump is the only thing standing in her way."

The development comes as a critical time in the 2016 presidential contest

The first debate is on Monday and Election Day is less than seven weeks away. Early voting has already begun in some states. Trump and Democrat Hillary Clinton remain locked in a tight race as both struggle to unite their partiesbehind them. Trump, in particular, has been branded as a phony by hard-line conservatives, Cruz among them, who see him more as a political opportunist than a true Republican.