WASHINGTON — Need evidence there's no clear path to the Republican presidential nomination? Consider the competing messages some likely candidates delivered on Sunday's talk shows.

Wisconsin Gov. Scott Walker, relatively inexperienced on foreign policy, and Sen. Lindsey Graham of South Carolina, a veteran on the issue, appeared open to sending U.S. ground forces take on Islamic State militants. At the same time, former Arkansas Gov. Mike Huckabee was trying to win voters by likening being gay to using alcohol or profanity.

Each approach could ultimately prove successful; both highlight the challenge for the crowded field of potential contenders to stitch together a winning coalition of national security hawks, evangelicals, social conservatives, business leaders and moderates who make up the modern Republican Party.

As the 2016 campaign is beginning to gel, each prospective candidate is testing appeals to voters and, perhaps more important at this early stage, donors. No one has taken the formal step of becoming a candidate, yet all are trying to hone a message.

Take Walker, who has garnered increased interest among the party's conservatives. He delivered a well-received speech to Iowa conservatives last weekend.

The Iowa Poll, conducted last week for The Des Moines Register and Bloomberg Politics, showed Walker atop the list of potential candidates but statistically even with Huckabee, Sen. Rand Paul of Kentucky and 2012 nominee Mitt Romney when likely caucus goers were asked their top choice for president. The poll was taken before Romney announced he was not running.

That only has increased the unsettled nature of the campaign.

Walker spent his weekend in Washington, wooing party leaders and recruiting aides to a likely campaign. In remarks on Friday — and then again on Sunday — Walker was seeking to cast himself as more than just a Midwestern governor who rolled back unions' bargaining rights.

"We need to take the fight to ISIS and any other radical Islamic terrorist in and around the world," Walker said Sunday.

Pushed on how he would combat the Islamic State militants, Walker could only say, "We have to be prepared to put boots on the ground if that's what it takes."

That position put him in line with another 2016 hopeful, Graham.

"An aerial campaign will not destroy ISIL," the South Carolina Republican said, using another acronym for the Islamic State. "You are going to need boots on the ground, not only in Iraq but Syria."

But that position could prove troublesome for the political fortunes of Walker and Graham. After more than a decade of war in Iraq and Afghanistan, polls show most Americans, including Republicans, wary of greater U.S. involvement in conflicts overseas.

With a more domestic outlook, Huckabee is trying to hone a message that plays well with social conservatives. It's a tactic he used during his 2008 campaign, one that helped him solidify his standing in first-to-nominate Iowa.

Huckabee said Sunday that being gay is akin to choosing to drink alcohol or use profanity — lifestyle choices he says are appealing to others but not to him.

The former Baptist pastor also claimed that forcing people of faith to accept gay marriage as policy is the same as telling Jews that they must serve "bacon-wrapped shrimp in their deli." That dish would run afoul of dietary rules, much as Huckabee sees asking Christians to accept same-sex marriages as contrary to biblical teaching.

"We're so sensitive to make sure we don't offend certain religions, but then we act like Christians can't have the convictions that they have had for over 2,000 years," Huckabee said on Sunday.

Defending Christians' rights is a staple of Huckabee's pitch and wins him many fans among the deeply conservative corners of Iowa. But same-sex marriage has lost some of its potency since he used social issues to win Iowa's caucuses in 2008; gay marriages are now legal in Iowa.

Huckabee has steadfastly opposed rights for gays and lesbians, although research has found a biological basis for their attraction to others of the same sex.

"I don't chuck people out of my circle or out of my life because they have a different point of view. I don't drink alcohol, but, gosh, a lot of my friends, maybe most of them, do. You know, I don't use profanity, but, believe me, I have got a lot of friends who do," Huckabee said.

Walker spoke to ABC's "This Week." Graham appeared on CBS' "Face the Nation." Huckabee spoke on CNN's "State of the Union."

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