The Florida senator made the comments during an interview on Fox News in which he said Republicans needed to consolidate their efforts or else Trump would become the runaway nominee.
"Last time, Mitt Romney got over 50 percent, so Donald Trump actually underperformed [what] Mitt Romney did, not once but twice in this state," Rubio said. "Right now we have a situation where the majority of the Republican electorate, the majority of Republican voters in this country, do not want Donald Trump to be the nominee."
In the Nevada caucuses on Tuesday, Trump won 14 delegates with 45.9 percent of the votes. Rubio beat Texas Sen. Ted Cruz for second place, winning seven delegates with 23.9 percent of votes to Cruz's six delegates with 21.4 percent.
"Until there's some consolidation here, you're not going to have an alternative to Donald Trump," Rubio said.