OVERLAND PARK, Kan. (CN) - In his last rally before a humiliating defeat in Saturday's Republican caucuses in Kansas, Sen. Marco Rubio misread the electorate and his opponents.
He focused his argument almost entirely on rival Donald Trump, who came in second, and failed to attack the eventual winner Ted Cruz, who emerged as the strongest alternative to a Trump candicacy.
"If you elect me, I will win," Rubio told a packed ballroom at the Marriott Hotel in Overland Park, a suburb in the Kansas City area, on the eve of the State's Republican caucus.
"We cannot win with a nominee that two-thirds of Republicans refuse to support," Rubio said, referring to Rep. presidential candidate Donald Trump, the frontrunner among Kansas voters.
This week the focus of the Republican race is on Kansas, where 40 GOP convention delegates are at stake Saturday.
While that's not many in the context of the 1,237 votes needed to win the Republican nomination, Kansas' caucus returns on Saturday, combined with Saturday caucuses in Maine and Kentucky, along with a primary in Louisiana, could bring Trump's Super Tuesday momentum to a standstill.
A poll earlier this week by the Trafalgar Group shows that among likely Republican caucus-goers, Donald Trump holds 35 percent support, Sen. Ted Cruz is at 20 percent and Rubio trails with 16 percent support. Ohio Gov. John Kasich's support stands at 12 percent.
But another poll conducted last week by the Docking Institute of Public Affairs and Fort Hays State University showed also showed that a full third of Republicans were undecided voters.
Some at the Rubio rally couldn't stomach the thought of Trump as the Republican nominee.
"I don't want him to win because he doesn't represent GOP values," Miriam Maldonado of Olathe. "He's nasty."
Rubio's Overland Park stop was his third rally on Friday, campaigning in Topeka with Gov. Sam Brownback Friday morning and competing for the crowd's attention during the final minutes of a Wichita State basketball game that afternoon.
Around 2,500 people signed up to attend the Overland Park rally, campaign officials said.
Gov. Sam Brownback joined Rubio at the rally, alongside New Mexico Governor Susana Martinez, former Pennsylvania Sen. Rick Santorum and Kansas Senator Terry Bruce.
"Marco needs the momentum to pick up Florida and completely change this race," Santorum told supporters. "That can start here tonight."
Santorum's introduction of Republican Gov. Same Brownback drew applause but also a long and loud chorus of boos from the Republican crowd.
Brownback is the least popular governor in America, according to a November 2015 poll by Morning Consult, a politics and policy news organization. He has been criticized for his tax policies that contributed to the state's budget troubles and underperforming revenues.
"Marco Rubio is going to win Kansas," Brownback declared to the crowd, praising Rubio's "Reagan-esque outlook of looking forward."
Rubio talked about how his mom worked as a maid and his father as a bartender, gave a shout out to military veterans and acknowledged the large number of young faces in crowd.
Rubio promised a return to limited government if elected president and vowed to "repeal and replace Obamacare once and for all."
College student Austin Gridley, 20, traveled 120 miles from Columbia, Mo. to attend the rally. Rubio's immigration policy appeals to Gridley, who said he'd like to have someone younger in the White House.
Another student, Wyatt Steed, 22, likes Rubio's immigration policy. "He's not completely shutting everyone out," he said.
Rubio made sure to take a few swipes at Trump on Friday.
"I did not find my success because I inherited a million dollars," he said, and later joked that Trump thinks the nation's nuclear weapons triad "is a rock band from the 80s."
"I like it that he stands up to Trump," said Mayra Arroyo of Leavenworth. "It's not fair that Donald Trump gets to behave like that and isn't held accountable. [Rubio] gives him a taste of his own medicine. I like how he stays professional."
Robert Garmitchell, a retired math professor from Overland Park donated $1,000 to Rubio's campaign, as well as smaller donations to other candidates who have since left the race.
His support for Rubio isn't contingent on anything about Trump, said Garmitchell. He'd be "very sad" if Trump got the nomination but would still vote for him. "The issue is not about conservative or liberal. It's about who can solve the country's problems," he said.
Rubio closed his speech with a warning that a Hillary Clinton presidency would be a time that historians would one day look back on and shudder
"The last eight years have been a disaster," Rubio said, calling Barack Obama the worst president since Jimmy Carter. "If Hillary Clinton is elected, we will remain on the road we are on.
"You have a choice tomorrow at a caucus near you. If we nominate someone like Donald Trump, he will lose," Rubio declared. "There's no doubt about it. A consequence of that will be a President Hillary Clinton.
"If you elect me, I will win. Democrats know that, and that's why they attack me more than any other candidate."
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