The head of the Koch brothers' flagship political organization says a Republican winning the presidency is becoming a higher priority for more of its members, suggesting a rift between pragmatists and ideologues.

Americans for Prosperity President Tim Phillips said conservative fatigue after George W. Bush's presidency in 2008 and overconfidence in efforts to beat President Barack Obama in 2012 have focused more members on winning back the White House than he's seen since the group formed a decade ago.

"I do think there is a sense of urgency about the future," he said, "that you owe it to your principles to win for those principles."

It's hard to tell how deep the divide between pragmatists and more ideologues runs, although reactions were mixed at the group's annual conference in Ohio Friday and Saturday. Five presidential candidates addressed the roughly 3,600 conservative activists from around the country, from tea party star Ted Cruz to Jeb Bush, a relative newcomer to the group's events.

"I think people are coming to the conclusion that there is no perfect candidate," Americans for Prosperity Iowa Director Drew Klein said.

Americans for Prosperity spent more than $30 million on television advertising in 2012 attempting to defeat Obama. The group does not plan to endorse a candidate in the Republican primary, but its leaders haven't decided whether they will advertise on behalf of the 2016 GOP nominee, Phillips said.

Based on the variety of reactions to the candidates by members who attended the conference in Columbus, they would have a long way to go to reach consensus.

"I'm listening to everyone," said Leona Poston of Kentucky. "We need to win this time."

Cruz, the tea party favorite since his 2012 election, sparked deafening cheers in the Columbus Convention Center auditorium even before he took the stage, entering to the 1980s power anthem "Eye of the Tiger." During his speech Saturday, he punched at the lines promising to "repeal every word of Obamacare" and "rip to shreds this catastrophic Iranian nuclear deal."

Florida Sen. Marco Rubio stooped to shake the outstretched hands of fans as he took the stage to speak Saturday.

By contrast Bush, who spoke the day before, earned far fewer cheers than either Cruz or Rubio and received mostly polite applause from the anti-tax, economic conservative audience.

Conservative industrialists Charles and David Koch have cracked the door open for Bush, who served two terms as Florida governor before the rise of the group that helped launch the political rise of some of Bush's 2016 rivals.

Members voiced reservations about the former governor's support for Common Core education standards, which some in the group misunderstand to be a federal government mandate. And a handful chanted their opposition as he left the stage.

David White of Ohio was not impressed. "He used his time to try and rearrange perception of his record in Florida," White said.

But some said they were open to supporting Bush, who has only recently begun attending the group's gatherings and was making his first appearance at its annual conference.

"Bush can raise the money to win," said Kelly Gunderson of Minnesota, who opposes Common Core, but was "pleasantly surprised" by Bush. "And I would say I can be with someone who I support 80 percent of the time."