Updated

Many of the Republican candidates seeing the White House in 2016 are in Iowa Saturday, wooing early caucus-goers.

The event is taking place at the Iowa State Fairgrounds.

Marco Rubio continued to poke at Jeb Bush during the forum, as the rivalry between the two Florida Republicans intensifies.

The Florida senator told more than 1,000 people in attendance: "We must turn the page and allow new leaders and new principles."

The subtle shot at Bush is part of Rubio's appeal to voters tired of the Bush family owning the past two Republican presidencies.

Bush is the son and brother of former presidents.

"There is another road... that will allow us to be the freest and will allow us to leave our children better off," Rubio also said, with himself in mind.

Texas Sen. Ted Cruz got applause when he railed against a new GOP adversary, CNBC, which is facing sharp criticism about how it handled Wednesday's debate.

Cruz is proposing that conservative commentators Sean Hannity, Rush Limbaugh and Mark Levin moderate a Republican presidential debate.

"What you wouldn't have is a bunch of left-wing operatives," Cruz said.

He also criticized the CNBC moderators for their questions, saying "How do you have a debate about the economy and not mention the word 'ObamaCare'? ... But we had plenty of time to talk about fantasy football."