Republican Sen. Ted Cruz sounds increasingly like he's made up his mind to run for president in 2016, telling an influential gathering of conservative activists Saturday that "we are part of a grassroots fire that is sweeping this country."

"I'm convinced we're going to win in 2014, and 2016 is going to be even better," the Texas Republican said during a summit of Americans for Prosperity, the political arm of the billionaire GOP donors Charles and David Koch. "And in the year 2017, a Republican president in the Rose Garden is going to sign a bill repealing every word of Obamacare."

Cruz joked about inviting President Barack Obama to the border to see where thousands of unaccompanied immigrant children have poured into the U.S. The president declined such an invitation from Texas Gov. Rick Perry.

"I figured out the only way there is a chance in heaven he might come, I'm inviting him to come to a golf course," Cruz said.

Cruz offered a way to deal with Islamic State militants in Iraq. "ISIS says they want to go back and reject modernity," he said. "Well, I think we should help them. We ought to bomb them back to the stone age."

When the crowd of more than 3,000 at a hotel ballroom serenaded him with calls of "Run Ted, Run!" he offered a quip: "Oddly enough, that's the same thing my wife, Heidi, says to me when I go to the gym."

Cruz ignored direct questions about a presidential campaign when he met with reporters after the speech.

He told the conservatives, "Each of you are here because we are part of a grassroots fire that is sweeping this country" and added: "We are building an army."

Two other possible 2016 presidential hopefuls, Perry and Sen. Rand Paul of Kentucky, spoke to the summit on Friday.