Turnout is always a big factor, and in this Texas race even more so, as Democrats will need to overcome historically low voter turnout in the state in order to push a win over the incumbent Cruz.
Jake Gyllenhaal wore a "Beto for Senate" T-shirt in a Facebook post that also endorsed other high-profile Democrats, including Stacey Abrams in Georgia and Andrew Gillum in Florida. "Is that in the GOP health-care plan?"
"My confidence is in the people of Texas", O'Rourke told reporters on Monday night, moments before staging a raucous rally with Mariachi band at the University of Texas at El Paso, mere blocks from his home. "And so, yeah, I feel good".
However, the polls gave Cruz a consistent lead in the race.
The tightness of the race meant Cruz had to lean on his former political rival - President Trump, whom he competed against in the 2016 Republican presidential primary.More news: Newlywed couple killed in helicopter crash hours after wedding
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O'Rourke says an upset win would prove that "Texas is not going to be governed by our fears".
But Triumph seemed ready for the remark and hit Cruz with one parting shot. It's the time for action. "Please know this: we will ensure border security". Shortly before they were about to start, officers on the scene said they were postponed. "They're filled with rage and hatred for the president".
Cruz, who was first elected to the U.S. Senate in 2012, has been a prominent, if not contentious, figure in the Republican Party. His challenge to Cruz was bolstered by more than $70 million in donations from across the country, making the race the most expensive Senate contest in US history. "The Trump administration, and by extension the (Texas Gov. Greg) Abbott administration, have done quite enough to intimidate voters without staging military rehearsals on Election Day".
Throughout the campaign, Cruz has assured voters that Texas is and will remain a conservative stronghold, frequently dismissing O'Rourke's media attention as hype.