Texas Sen. Ted Cruz waded into 2016 presidential politics Friday with stops in Iowa where he called on Republicans to do more than just grandstand on issues like defunding Obamacare.

Speaking to Christian leaders and ministers at a "pastors and pews" event in Des Moines organized by evangelical leader David Lane, Cruz said that Republicans have to do more than just talk about fighting the president on issues like Obamacare. And he called on the grassroots to mobilize and force Republicans to bring about change to Obamacare as they did during the gun control debate in the spring.

"Belief, saying I believe in something, is not sitting there quietly doing the golf clap," said Cruz who was joined at the event by another potential 2016 candidate, Sen. Rand Paul.

At one point, according to the Des Moines Register, Cruz said that Congress could stop Obamacare by removing funding when the spending resolution comes up for a vote in September.

"President Obama will scream and yell and blame those mean, nasty Republicans for wanting to shut down the federal government," he said, but it could be done.

When one in the audience asked, "What are the chances of that?" Cruz acknowledged, "the chances of that today are zero."

The reason, he added: "There are a lot of politicians who like to do symbolic things that are destined to failure so they can come back and say, 'See, see I'm standing for the principles I told you I was.'"

But he said that grassroots mobilization can change that and he called on Republicans to pressure their elected officials. A similar effort worked to help kill the gun control bill before the Senate in the spring.

Paul Bedard, The Washington Examiner's "Washington Secrets" columnist, can be contacted at pbedard@washingtonexaminer.com.