Inside the Beltway, Newt Gingrich is well-known as a provocateur, a novelist, and a futurist. But a national-security heavyweight? Not so much.

On the campaign trail, however, the former speaker is challenging the conventional wisdom. Beginning this week, according to campaign sources, the rising contender will make a concerted play for national-security conservatives.

For Gingrich, the strategic shift serves two purposes: It reminds voters about an often unnoticed part of his record, and it shows Mitt Romney — who is in a dead heat with Gingrich in the latest polls — that, on national security, he has competition.

Romney, a former Massachusetts governor, has frequently highlighted national security, penning a bestseller, No Apology, that outlines his worldview. He has also enlisted boldface names, such as former CIA director Michael Hayden, to his advisory team. Yet Romney is not experienced on foreign policy, which leaves room for Gingrich to assert himself, observes a source close to Gingrich.

On economic and social issues, Gingrich and Romney share conservative beliefs, broadly speaking, even if they have contrasting policy platforms, the source notes. National security, with the related question of leadership, allows for bolder colors. “Newt will ask voters to think big on national security, to go beyond talking about budget numbers, asking them to contemplate what the country needs to do to confront our enemies, especially radical Islamism, with a grand strategy,” the source says.

In turn, by talking about such themes, “telling the truth” to Americans about foreign threats, Gingrich may be able to carve out a unique space in the GOP field.

Romney, who outlined his national-security ideas at the Citadel in October, has frequently used military metrics as a central plank, from naval shipbuilding to missile defense. When it comes to Islamism, he has been forceful but avoided Gingrich’s firebrand phrases.

Gingrich allies bet that GOP voters want to hear about more than blue-water ships. As they see it, Romney may have voters nodding in agreement, but no one is cheering the approach. Gingrich also wants to modernize the fleet, of course, but politically, he will lead with ideas.

In coming months, by taking on controversial national-security matters without pause and blasting the Obama administration with vigor, Gingrich could cut a compelling figure, advisers say, boosting his electability and affirming his policy chops.

“This primary may come down to the ‘red-phone question,’ which is, ‘which candidate do you want answering that late-night call when there is a crisis?’ With his years of leadership at the federal level, and his decades of outlining security-policy solutions, the clear answer is Newt,” one adviser says. “On Tuesday, he’ll begin to point this out.” Tonight’s debate, sponsored by CNN with the Heritage Foundation and the American Enterprise Institute, will focus on national security.

Gingrich, for his part, will blend in some biography with the rhetoric. His aides say he will use his speaking time, if possible, to talk about his previous leadership roles, such as serving on the Defense Policy Board during the George W. Bush administration, where he worked closely with Donald Rumsfeld, then the Pentagon chief. His years as a war lecturer at the United States Air Force’s Air University and the National Defense University may also be mentioned.

Most likely, out of all of his experiences, he will cite his work on the Hart-Rudman Commission, which was chartered in the late 1990s to map a national-security strategy for this century, as an example of how he sees national security, using history and politics to make his case.

But before he takes the stage, Gingrich will unveil his own national-security advisory board. Two of the leading names involved are R. James Woolsey, a former director of central intelligence, and Robert McFarlane, who served as national-security adviser to President Reagan. David Wurmser and Stephen Yates, two former advisers to Vice President Cheney, have also signed on. So have Bill Schneider, Norman Bailey, and Ken deGraffenreid — all former Reagan advisers. A handful of scholars and analysts complete the team.

Woolsey, a longtime friend of Gingrich, tells National Review Online that the former Georgia lawmaker has what it takes to win over hawks. “Newt is really a military historian,” he says. “He looks at things from a historian’s perspective, how societies move and how they change.”

Woolsey also praises Gingrich for embracing science and technology as necessary for sustained U.S. national-security prowess. An adviser points out that Gingrich has been highlighting this theme for years. In a 2007 essay for Strategic Studies Quarterly, for example, Gingrich outlined his big-picture take, writing that “history is littered with great powers that watched their preeminence pass to others as they failed to adapt to scientific and technological change.”

“The American military officer, therefore, has a special responsibility to do all within his or her capability to lead America and keep it the leading power in science and technology on the planet,” he continued. “Leading the world in science and technology is the fundamental challenge of American national security for our generation.”

Gingrich sources acknowledge that months ago, when the candidate was struggling in the polls, taking the time to champion the candidate’s national-security strengths was not possible. Survival — through strong debates and making the best of a shoestring budget — was the lone goal. Now, with growing national support and a little more than a month until the Iowa caucuses, the campaign has the ability and resources to make a national-security splash.

Polls back up that confidence. A CNN/ORC International poll released on Monday shows Gingrich as the favorite on national security; 36 percent of respondents said he is “most qualified to be commander in chief,” compared to 20 percent for Romney. A CBS News poll earlier this month showed Gingrich as the candidate Republicans “trust most to handle an international crisis,” besting Romney 31 percent to 19 percent. To be sure, other polls place Romney above Gingrich on this issue, but within Gingrich’s camp, the CNN/ORC and CBS News polls are hints of what’s possible, reflecting what advisers describe as a growing movement toward Gingrich.

So tonight, the battle for the security crown begins anew, at least for Gingrich.

— Robert Costa is a political reporter for National Review.