NEW YORK (AP) ― Jeff Flake and Martin Heinrich were willing to go to great lengths to prove that a Democratic and Republican U.S. senator could work together.

Like halfway around the world. The freshman senators traveled to an uninhabited tropical island north of Australia this summer for a week documented by the Discovery Channel on a special that airs Wednesday at 10 p.m. ET.

The result is a lot like “Survivor,” only without Jeff Probst leading them through challenges. Thankfully, they’re neither naked nor visibly afraid. Flake, an Arizona Republican, and Heinrich, a Democrat from neighboring New Mexico, try to build a fire, find shelter and hunt for food and water.

They hope their broader point ― that two politicians can oppose each other on policy yet work together to accomplish something ― isn’t lost on viewers or their colleagues.

The idea began as a joke that quickly became real. The men are already fit, outdoors types, and Flake spent a week alone on another Marshall Islands spot five years ago in what his wife called his midlife crisis. The senators started chatting about hobbies one night on the Senate floor during a long session.

“I showed him pictures of fish that I’d speared,” said Flake, 51. “He showed me some that he did and they were much bigger. So I thought, ‘This guy could be useful.’”

Once they decided to go, they thought they‘d bring some cameras to record the experience and talked to Discovery about whether the network would be interested. Yes, but Discovery wanted to send its own production team.

“That was the point at which we lost control,” quipped Heinrich, 43.

There’s some truth behind that remark. One thing politicians hate to cede is control. They kept the whole thing secret from all but a few people until after they got back late this summer, and felt the pressure while there.

“Neither one of us wanted to be the guy who taps out on Day 3 or can‘t hold up his end of the bargain,” Heinrich said.

Even without Probst, the two had a number of challenges. Finding food and fresh water was tough. Heinrich was disgusted by the amount of pollution that had washed ashore on their island, but the found objects undeniably helped sustain them.

It was an educational experience for both.

“I learned that Martin’s fire-starting skills are a lot better at home than on the island,” Flake said.

“I learned that Jeff swims a lot faster when there are sharks behind him,” Heinrich said.

Their most important accomplishment was building a sense of trust. The men, both former House members elected to the Senate for the first time in 2012, have heard all the old Washington stories of political foes who fought during the day and socialized at night, but said that‘s more difficult today.

Republicans and Democrats have fewer opportunities to know each other. Most are commuters, gone when the Senate isn’t in session. Evenings are filled with political fundraisers, and Flake said during sessions, GOP senators often have three lunches scheduled each week with each other. Democrats have two (“Quicker studies,” Heinrich joked).

Add in a political atmosphere that doesn’t reward conciliation and it’s a recipe for gridlock.

Following the airing of “Rival Survival,” the senators said they would send a letter to colleagues urging that they all get together socially at least once a month, if not once a week, to build relationships and help to work with one another.

They also wouldn’t mind seeing some colleagues try what they did.

“We have a list,” Heinrich said. “There’s a list of people we think will come back working better together, and a list of people we think the Senate would work better without.”