As President Donald Trump and Texas Republican Sen. Ted Cruz shared a stage Monday evening in Houston, the former bitter rivals proved that one should never say never in politics.

“We had our little difficulties,” Trump told rallygoers at the Toyota Center, before calling Cruz now a “good friend.”

The unlikely allies joined forces as Republicans look to hold on to a Senate seat as the party tries to retain or even expand its two-seat majority. Doing both requires convincing Lone Star State voters to send Cruz back to Washington. The president lavished praise on the man he once called “Lyin’ Ted,” referring to Cruz as “Beautiful Ted” and “Texas Ted” even before departing the White House.

Trump flew to Houston to stump for Cruz as the senator looks to avoid being upset by Democratic Rep. Beto O’Rourke. Polls showed a tight race all summer, but have recently shown Cruz opening a wider lead. Inside Elections with Nathan L. Gonzales rates the race Tilts Republican just 15 days before Election Day.

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Trump went on the attack against O’Rourke, calling him a “phony” who “wants to take away your guns.” If he wins, the president said, “your Second Amendment is in trouble.”

Trump told the crowd that Cruz has “defended” the country’s borders and helped him pursue his agenda. “Ted is leading the charge in Congress for more tax cuts,” he added.

The president added some detail to his idea of Republicans introducing — and somehow passing despite both chambers being on recess — more tax legislation before the midterms. He told the crowd it would be a 10 percent middle-class rate reduction, warning that Democrats would push a “big” tax hike if they win more power in Washington.

Trump also floated the idea that if Republican voters want an investigation of Hillary Clinton, the lone way might be to nominate her to the Supreme Court. The crowd booed loudly as he riffed about how Democrats treated Justice Brett M. Kavanaugh during the confirmation process.

He also debuted a new line, saying the midterms will be about “the caravan, tax cuts and Kavanaugh” — the first a reference to a group of migrants traveling in a caravan through Central America. The Toyota Center crowd roared. 

He later blamed congressional Democrats for the approaching migrant caravan, and accused them of wanting to give undocumented immigrants “free welfare and the right to vote.”

And in yet another 2020 preview, Trump lashed out at potential Democratic presidential candidates. “I can’t call her ‘Pocahontas,’ she doesn’t have any Indian blood,” he said of Massachusetts Sen. Elizabeth Warren after she released a blood test with less-than-definitive conclusions about her claims to Native American ancestry.

Trump joked that he asked Texas leaders to name a proposed dam in Houston to help with flood waters during storms the “Trump Dam,” indicating he might approve a request for $10 billion in federal funding.

Cruz attacks

At his campaign rallies so far this year, Trump has often turned the blue podium with the presidential seal over to GOP candidates after whipping the crowd into a frenzy. But on Monday, Trump sent Cruz out to address the audience before he even entered the arena.

“God bless Texas,” Cruz said as he took to the microphone. “And God bless President Donald Trump.”

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Cruz painted O’Rourke as a “big-government, gun-grabbing liberal” who has policy stances that would appeal more to voters in San Francisco than Texas.

Noting that early voting is underway, Cruz described the coming election as a key point in which voters will decide, “Do we embrace freedom or give into tyranny?” He also said the GOP will deliver “jobs” and cast the Democrats as “mobs.”

“Here in Texas, we celebrate when it rains, we don’t tax you for it,” he said, accusing O’Rourke of once voting for a “rain tax.” He hit his opponent as a supporter of higher taxes and measures that would hurt the oil and gas industry, as well as regulations that would hurt businesses and workers.

And he painted his race as the embodiment of the decision voters will make in 15 days, saying, “There is not a … race in the country” with a clearer difference between candidates on immigration. “We need to build the wall,” Cruz roared of Trump’s proposed southern border barrier. The crowd roared louder.

Cruz tried to tie O’Rourke to House Minority Leader Nancy Pelosi, and California Democratic Rep. Maxine Waters, using the word “liberal” over and over to describe his opponent. And he said O’Rourke is “running to the left” of liberal senators such as Warren and Vermont’s Bernie Sanders, also a potential 2020 contender.

Complicated history

Cruz and Trump have met several times since the New York real estate executive and reality television host won the White House. The Texas senator at times has defended some of Trump’s more controversial statements and policy moves.

To be sure, things were not always this supportive and chummy between the former 2016 GOP primary rivals.

Candidate Trump dubbed the senator with the aforementioned “Lyin’ Ted” moniker during the 2016 primaries, and even suggested Cruz’s father was involved in the assassination of former President John F. Kennedy. Trump also took several jabs at Cruz’s wife, prompting the senator to call him a “sniveling coward.”

In May 2016, Cruz came back with a vengeance, calling Trump a “pathological liar” and “utterly amoral.” He also dubbed his primary foe “a narcissist at a level I don’t think this country’s ever seen,” before branding Trump a “serial philanderer.”

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“He describes his own battles with venereal diseases as his own personal Vietnam,” Cruz said then, a jab at Trump’s quips about his sex life after receiving deferments because of bone spurs during the Vietnam War. And in a high-profile snub at the Republican convention that August, Cruz was given a prime speaking slot — but he opted against clearly endorsing the nominee, Trump.

Not ‘biggest stadium’

Two years later, the two Republicans were back on the campaign trail, this time sharing a stage at the Toyota Center in Houston, an arena that is home to the NBA’s Rockets and seats around 19,000. Trump in late August vowed to hold a rally for Cruz at the “biggest stadium in Texas we can find.”

Fans of the state’s Dallas Cowboys franchise — the self-described “America’s Team” — would consider the team’s AT&T Stadium as the biggest in Texas. The nine-year-old stadium’s official football capacity is 80,000 — but crowds of 108,713 (NBA), 105,121 (NFL) and 101,763 (WWE) have packed into the venue since its May 2009 opening.

Houston also boasts two larger venues: the MLB Astros’ Minute Maid Park (record capacity: 44,203) and NFL’s Texans’ NRG Stadium (record attendance: 80,020). The state also has a list of college football stadiums that can fit larger crowds than the Toyota Center.

Saying it had over 100,000 online ticket requests, the Trump campaign organization organized a pre-rally “Texas tailgate” with country music bands and giant screens on which attendees could watch the president’s remarks inside the arena.