Washington (CNN) Donald Trump questioned his Christianity, insulted his wife's appearance, suggested his father was involved with President John F. Kennedy's assassination and nicknamed him Lyin' Ted.

It's all water under the bridge now, as Cruz fights to hold his Senate seat in deep-red Texas and the President struggles to keep a Republican majority in the Senate.

Trump has volunteered himself, as well as two of his most high-profile surrogates -- his children, Don Jr. and Ivanka -- to appear alongside the Texas senator as his re-election race tightens

Since the bitter 2016 primary, Cruz has extended himself as an ally to the administration, putting aside their awkward history to have dinner at the White House with his family last year. Cruz has since been spotted dining about town with Ivanka Trump and Jared Kushner.

Looking forward to visiting @NASA_Johnson tomorrow in #Houston with @IvankaTrump & @JimBridenstine to discuss the great work being accomplished by @NASA to advance human space exploration. — Senator Ted Cruz (@SenTedCruz) September 19, 2018

On Thursday, Ivanka Trump, a senior adviser to the President, will join Cruz in his hometown of Houston for a visit to the Johnson Space Center.

"Looking forward to visiting @NASA_Johnson tomorrow in #Houston with @IvankaTrump & @JimBridenstine to discuss the great work being accomplished by @NASA to advance human space exploration," Cruz tweeted

The NASA visit is official business, not a campaign event; Ivanka Trump has thus far largely aimed to avoid entanglement in the 2018 midterm races, opting instead to travel the country touting tax reform, the administration's working family agenda, workforce development and other initiatives, including STEM education.

But the President's eldest daughter's trip to Texas is likely to garner positive media attention for Cruz, who faces Democrat Beto O'Rourke in November.

Ivanka isn't the only Trump to travel to Texas alongside Cruz. Her brother, Donald Trump Jr., will join the Republican senator in Texas in the coming weeks.

And the President has vowed to pull out all stops in support of his former rival.

I will be doing a major rally for Senator Ted Cruz in October. I'm picking the biggest stadium in Texas we can find. As you know, Ted has my complete and total Endorsement. His opponent is a disaster for Texas - weak on Second Amendment, Crime, Borders, Military, and Vets! — Donald J. Trump (@realDonaldTrump) August 31, 2018

"I will be doing a major rally for Senator Ted Cruz in October," he tweeted last month, adding, "I'm picking the biggest stadium in Texas we can find. As you know, Ted has my complete and total Endorsement. His opponent is a disaster for Texas - weak on Second Amendment, Crime, Borders, Military, and Vets!"