Now, all he has to do is convince the rest of his party that he's the only person who can actually stop real estate mogul Donald Trump.
It's an argument the Texas senator has been making for weeks, but with the critical states of Florida, Ohio, Illinois, Missouri and North Carolina voting next Tuesday, there's a new sense of urgency in his campaign to get Ohio Gov. John Kasich and Florida Sen. Marco Rubio out of the way and create a two-man race.
"If you don't want to see Donald Trump as the nominee, if you don't want to hand the general election on a silver platter to Hillary Clinton and the Democrats, then I ask you to join us," Cruz said at a rally Wednesday in Florida. "If you were a Jeb (Bush) supporter, If you are a Marco supporter now, if you're a Kasich supporter, we welcome you to our team."
With the #NeverTrump campaign charging on and party leaders sounding increasingly alarmed about a possible Trump nomination, Cruz -- in theory -- should be well-positioned to garner the party's blessing.
But GOP strategists, leaders and donors continue to express deep reservations about throwing their support behind the Texas senator, whose White House bid has exposed his unpopularity within the GOP establishment, including among his colleagues on Capitol Hill.
Both Rubio and Kasich enjoy more support from national party leaders but have lagged behind at the ballot box and are focused squarely on Tuesday and the winner-take-all contests in their respective home states of Florida and Ohio.
Katie Packer, a GOP operative leading the anti-Trump super PAC called Our Principles PAC, said her group's primary goal is to deny Trump the 1,237 delegates needed to win the GOP nomination outright. An important part of that strategy, she said, is ensuring that Rubio and Kasich win their home states next week.
"Our best chance of stopping Trump is that he doesn't win Ohio and he doesn't win Florida, and we happen to have two very strong, favorite-son candidates that are in the race," Packer said of Kasich and Rubio. "So why would we want either of them to not be in it next Tuesday?"
Veteran GOP strategist Charlie Black, who has worked on multiple presidential campaigns, said it would be unwise to rally behind any GOP candidate before Tuesday. And though he vowed to back the eventual Republican nominee, Black said he does not believe Cruz can win in the general election.
"We should have been calling March 15 Super Tuesday because that's the decisive day," Black said. "Should the party rally behind somebody, it should be Rubio or Kasich because either one of them could win the general election."
Kasich had hoped for a strong showing on Tuesday in Michigan, a state where he campaigned tirelessly, but finished a disappointing third. And the evening was particularly devastating for Rubio, who walked away without a single victory and didn't meet the threshold to pick up any delegates in Mississippi, Michigan and Idaho.
Meanwhile, Cruz finished in second place behind Trump in Michigan, Mississippi and Hawaii on Tuesday. Just three days before, Cruz denied Trump the sweeping, victorious night that the billionaire businessman had hoped for by winning the Kansas and Maine primaries as he chases the GOP front-runner in the delegate race.
Graham's kind words
There are signs that with more time, some Republican leaders may — however grudgingly — come around to supporting Cruz in the name of stopping Trump.
Lindsey Graham, who endorsed Jeb Bush after ending his own White House campaign, has been one of Cruz's most outspoken critics on Capitol Hill. But the South Carolina senator -- whom Trump has repeatedly mocked and insulted -- has started to suggest that it may be time for his party to rally around Cruz "as the only way to stop Donald Trump."
"As much as I disagree with Ted Cruz, if it came down to Donald Trump or Ted Cruz, I would be firmly in Ted's camp because I think he really is a conservative," Graham told CNN's Wolf Blitzer on Monday.
Graham made clear that he much prefers Rubio and Kasich over Cruz. But with a fierce anti-establishment fervor driving voters in 2016, Graham said he does not believe either Rubio or Kasich has what it takes to defeat Trump: "It seems to me that Ted has the most persuasive case thus far that he can take on Donald Trump and deny him the nomination."
But another former GOP presidential contender came out firmly in Cruz's camp Wednesday with no qualms attached. Carly Fiorina endorsed Cruz Wednesday, saying she is "kind of horrified by Donald Trump," adding she doesn't believe he will be the anti-Washington fighter he purports to be.
"There are some people in our party saying Donald Trump isn't so bad ... but he's a deal maker; he can make deals," Fiorina said at a Cruz rally in Florida
. "The truth is Donald Trump and Hillary Clinton are two sides of the same coin. They're not going to reform the system, they are the system."
This week, Cruz even picked up support from a member of the Bush family. Neil Bush, Jeb Bush's younger brother
and a well-known Houston businessman, signed on with Cruz's fundraising team.
But not many others have publicly followed course. And privately, plenty of GOP strategists have bristled at the Graham's suggestion that the time has come to build a coalition around Cruz. In addition to the establishment's dislike for the Texas senator, the genuine belief that the GOP race remains fluid is also holding back party operatives and donors from getting behind Cruz.
A Wall Street Journal/NBC poll out Tuesday showed Trump still leading nationally, but only by three points. And the details did not bode well for the New York billionaire.
In states with contests still to come, Trump was the top pick among 27% of likely GOP primary voters. He was followed by Cruz at 25%, Kasich at 24% and Rubio at 23%, putting all three of Trump's rivals within the margin of error of reaching parity with him. And all of his Republican rivals opponents would defeat Trump in one-on-one hypothetical match-ups.
Cruz has made his mark in Washington as a first-term senator by branding himself an ideological purist and by directly challenging party leadership (in a Senate floor speech last summer, Cruz famously accused the Senate's top Republican, Mitch McConnell, of lying). Over the years, he gained a reputation on both sides of the political aisle for being an obstructionist.
Close to a year after launching his White House campaign, Cruz has yet to pick up a single endorsement from a fellow Republican senator.
But Cruz surrogate Ken Cuccinel said the "theme that nobody likes Ted in Washington has been totally overblown." The former Virginia attorney general pointed to Graham's recent comments as a "reality check" for the GOP.
"That's tectonic," Cuccinelli said. "The fact that Lindsey Graham said what he said about getting behind Cruz -- and clearly the way he said it, if you watched the video, it was very authentic, it was very honest, it had all of his emotional reservations -- but it was a reality check."