Story highlights Super PACs backing Ted Cruz are scrapping a major media buy it once eyed in Florida because Marco Rubio is likely to lose there "all by himself," the groups say

Keep the Promise, the main cluster of independent groups backing Cruz, is preparing to spend millions of dollars in a quartet of states that vote on March 15

Washington (CNN) Super PACs backing Ted Cruz are scrapping a major media buy they once eyed in Florida because Marco Rubio is likely to lose there "all by himself," the group's leader says.

Keep the Promise, the main cluster of independent groups backing Cruz, is preparing to spend millions of dollars in a quartet of states that vote on March 15: Missouri, Illinois, Ohio and North Carolina. It is passing entirely on Florida, Rubio's home state, where he badly trails national front-runner Donald Trump in polls.

"We're no longer doing anti-Rubio ads in Florida, because it appears he can lose Florida all by himself," said Kellyanne Conway, the group's president. "He doesn't need our help."

Only about $1 million has been bought so far. But the groups are planning to buy up to $3 million more of television in North Carolina, Missouri and Illinois, to add to the more than $535,000 on digital advertising spent in those states as well as Washington, D.C. and Ohio, and the $435,000 on radio in North Carolina, Missouri, Illinois and Ohio. Republicans in D.C. vote on March 12.

Cruz forces had planned an incursion into Florida as part of an effort to deny Rubio the 99 delegates he needs in his home state to argue he has a viable path to the nomination. Cruz in recent days has intensified his argument that should Rubio remain in the race, it is likely to hand Trump the nomination by keeping the field splintered. Florida was seen as a chance to deliver a knock-out punch to the Florida senator on his own turf.

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