WASHINGTON -- If conservatives want to win the Republican primaries in 2016, they’d better unite -- early on -- around a favorite candidate. Otherwise, they may end up watching the GOP pick a moderate as the party’s presidential nominee -- again.

“By this time next year, I would be surprised and very disappointed if the majority of conservative leaders around the country hadn’t come together and decided, ‘This person is our best bet and we urge you to coalesce around this person,’” said Steve Deace, a conservative talk radio host from Iowa where the first-in-the-nation presidential caucuses are held.

No one has yet declared his candidacy, but the infighting already is underway. Sen. Rand Paul took to Twitter Friday to criticize Sen. Marco Rubio, calling him an "isolationist." The two -- who have both been mentioned as potential 2016 candidates -- differ on the Cuban trade embargo. Rubio, who is Cuban-American, says it should remain and was dismissive of Paul’s support for loosening the restrictions. 

Trading barbs over Cuba is a prime example of the kind of fights that break out in primaries. Most of the candidates have similar views on the big GOP issues like taxes and abortion. So when they find a place to disagree, it becomes a flashpoint.

In the past several election cycles, a swarm of right-wing candidates competed for money, attention and votes, canceling themselves out in the process. Instead of trying to defeat the establishment, the conservatives lobbed attacks at each other. That allowed a moderate to emerge -- Mitt Romney in 2012, John McCain in 2008 -- who then lost the general election, at least in part because of a lack of enthusiasm from the GOP base.

Deace said Republican conservatives can flip the script on moderates and let them duke it out while a conservative coasts to victory. There are likely to be several moderates this cycle. New Jersey Gov. Chris Christie  is working to put together a campaign. Former Florida Gov. Jeb Bush  is sending strong signals he’ll run. Plus sitting governors like Ohio’s John Kasich and Wisconsin’s Scott Walker will be vying for establishment support. And Mitt Romney might run again.

“The establishment is going to have quite a chore next year trying to figure out who their proxy is going to be,” Deace said. “Christie isn’t going to just roll over and play dead for Jeb Bush.”

And it might be difficult to get conservative candidates to give up as well.

“Uniting around a single GOP conservative candidate early would greatly assist efforts to get a conservative nominee, and it would also be lovely if the candidates pledged to drop all negative TV ads so the eventual nominee would be unbloodied,” said Larry Sabato, University of Virginia political science professor. “Neither thing is going to happen. Politics is war and alliances are difficult to forge.”

The biggest problem for conservatives who may want to rally behind one candidate is at this point the field is so large. Deace has yet to pick a favorite. He cautions against doing so too soon, saying the candidates need to be vetted fully and any potential “skeletons” discovered.

There are already seven conservatives who are seriously looking at a presidential campaign. Of course, all seven won’t last until votes are counted in Iowa; there are always a few who sputter out early. And there could be a few more who jump in late. But no one has yet distinguished himself as a strong candidate capable of taking on either a moderate Republican in the primaries or a Democrat in the general election.

There are likely to be at least four newcomers to the conservative field. Kentucky's Paul has begun to put together the basics of a campaign. He’s likely to benefit from his father’s two recent presidential runs, giving him a network of donors and staff. But his Libertarian-infused positions on foreign policy could cause him some problems as his response to the Cuba initiative showed.

Texas Sen. Ted Cruz is also starting to build a campaign team. His attempts to blow up any bipartisan efforts in Congress have earned him a lot of cred in conservative circles. But his abrasive personality has made many enemies inside the party in Washington.

Louisiana Gov. Bobby Jindal hasn’t made a secret of his presidential ambitions. But the two-term governor will have to answer a lot of questions about the economic problems in his home state.

There is also a chance political newbie Ben Carson could run. The retired neurosurgeon has become a popular figure among conservatives. A CNN poll of possible GOP contenders earlier this month showed him second to Bush, with 11 percent to Bush’s 14 percent. This week he traveled to Israel, a common international trip for likely candidates. But he's not widely known, so fundraising is likely to be a battle. 

Not surprisingly, former Pennsylvania Sen. Rick Santorum is exploring another campaign. He has mostly laid low for the last two years after losing the nomination battle to Romney, running a PAC he was able to use to weigh in on political issues and campaign for candidates in local races. Republicans have a history of nominating the guy who ran the time before (see Romney and McCain). But Santorum was wounded by ads attacking some some of his more controversial positions on social issues, and he will have to find responses.

Texas Gov. Rick Perry has also hinted he may run again. Perry’s 2012 campaign flamed out after he botched a debate. But he has a strong record. And after having run once, he has a better idea about how campaigns work and how he should hire staff.

Former Arkansas Gov. Mike Huckabee is also hinting at the possibility he could run again. Huckabee won the Iowa caucuses in a landslide in 2008, but struggled afterwards. Huckabee has spent much of the intervening eight years as a commentator, working on talk radio and Fox News. That work has bolstered his name recognition but is also a real liability. Thousands of hours of tape of him discussing every political issue under the sun provide the makings of a million attack ads.

Those seven candidates are the ones currently generating buzz. There are months left. After all, Romney didn’t get into the race until June 2011.

But if there is any hope for Republican conservatives, they will have a good idea who they are backing long before summer comes.