Supporters are lining up for President Trump's big rally in Texas, one whole day before the event will take place.

With Trump's 2020 campaign boasting "100,000+" people being interested in attending, lines of people outside the venue Sunday evening, shown spanning multiple blocks in photos tweeted by CNN's Betsy Klein, further indicate high enthusiasm for the event.

The people at the front of the line had reportedly been there since 10 a.m. local time.

The rally, set for Monday evening at the Toyota Center in Houston, is poised to be the most powerful boost yet for Sen. Ted Cruz, who will share the stage with the man he once opposed for the presidency.

The Republican incumbent faces a surprisingly fierce challenge from Rep. Beto O'Rourke, who is enjoying a surge of popularity in a typically deep red state and has seen big crowds for his rallies.

But momentum appears to be building for Cruz, who still has an edge in polling.

On Thursday, Trump’s campaign said it moved the Cruz rally to a bigger venue in Texas after citing an “unprecedented” demand for tickets. Trump’s 2020 campaign manager Brad Parscale tweeted the venue change, saying the response for tickets to Monday’s rally in Houston has been "HUGE and unprecedented."

The Toyota Center, which can seat up to 19,000 people for concerts, is far bigger than the previous venue, NRG Arena, which holds about 8,000 people.

In a tweet, former White House press secretary Sean Spicer commented on Klein's photos, saying to expect a "massive crowd" at the rally.

On Sunday, the Trump re-election campaign offered more positive news, claiming that because there was more than 100,00 requests online for tickets to the event, there would be a "Big Texas Tailgater" outside the venue, which would include food, music, and, of course, big screens for viewing the main event, which starts at 6:30 p.m. local time.

Further solidifying the good vibes for Trump and co., one of the president's most vocal detractors, lawyer Michael Avenatti, conceded Sunday he would not be holding the "resistance" rally in Texas he previously said would take place on the same day as Trump's due to a scheduling conflict.