Eight Republican candidates will gather for the billionth — oops, sorry, twelfth— time tonight in Washington, D.C. for a debate focused on national security.

View Photo Gallery: Eight Republican candidates gather for the twelfth time in Washington, D.C.

The festivities get started at 8 p.m. on CNN — we will ramp up the Fix live-blog around 7:30 p.m. — but in the meantime we thought we’d offer a few things to keep an eye on in tonight’s debate.

As always, your thoughts are welcome in the comments section.

* Romney gets (another) pass?: With the Iowa caucuses just more than 40 days away, it’s amazing how little incoming former Massachusetts governor Mitt Romney has had to dodge in these debates. There has been next- to- no sustained attack on his signing of a health care law in the Bay State, and the idea of Romney as a flip-flopping opportunist hasn’t been raised much either.

Former House Speaker Newt Gingrich, Romney’s biggest rival, pledged in a recent forum that he has no plans to attack Romney and it’s tough for any of the second-tier candidates — businessman Herman Cain, Texas Gov. Rick Perry — to hit Romney without risking a boomerang effect back on them.

Add to that mixture that the stated focus of the debate is national security — not the economy, health care etc. — and it looks increasingly likely Romney will skate through another debate without taking on any heavy criticism (or damage).

* Newt being Newt:Gingrich’s confrontational approach to the questions asked of him and his willingness to throw out red meat to the base — Fire Ben Bernanke! — in these debates has fueled his amazing rise back to the top of the Republican presidential field.

But, while those long-ball tactics fit the moment as Gingrich was scuffling along well behind the frontrunners, he’s not likely to get off so easily now.

His rivals and the debate moderators will try to get Gingrich to go beyond talking points and may even challenge him on some of his past positions on things like cap and trade and immigration. (Remember when CNBC’s Maria Bartiromo challenged Gingrich on health care and he had no answer?)

How Gingrich reacts will be telling. Does he take the barbs in stride and do everything he can to stay on his reform-minded message? Or does he turn into the churlish Gingrich of yesteryear? The latter is a decidedly less appealing image for prospective voters.

* Huntsman’s moment: At some point, the former Utah governor has to win a debate — or come somewhere close to it. To date, his debate approach seems more geared to winning over campaign hacks and the press — making a serious of VERY insidery jokes/references — than to actually persuading voters in New Hampshire (and elsewhere) about why he is the most plausible Romney alternative.

A debate centered on national security/foreign policy matters should afford Huntsman a chance to flex his impressive resume and make clear to viewers that he is one of the only (perhaps the only) person on stage who knows this set of issues intimately well, having served in three Administration — including the current one — in posts all around the world.

Huntsman’s problem is that he will need to find ways to insinuate himself into the main conversation of the night, which is likely to be driven by Romney and Gingrich. Because Huntsman is mired in single digits (to put it nicely) in national polling, he won’t likely get that many chances to make his mark. He needs to find ways to maximize those chances. If he can’t distinguish himself in this debate, it’s hard to see a place down the road where he will stand out.

* Rick’s’s low bar:Combine a series of lackluster debate performances — can anyone say “Oops”? — with a national security focused debate and there could be trouble for the Texas governor as he tries to start a comeback from the single-digit depths he has fallen to in the contest.

But, it’s also possible that Perry can use those below-low expectations in his favor. Perry was considerably better in the foreign policy-centric debate two weekends ago in South Carolina, a performance that suggests he may have finally found his footing in the campaign. (And, yes, it’s probably too late.)

Expect Perry to come out very aggressively — what other choice does he have? — and try to assert himself as the tough-talking, take-no-bs leader that hawkish Republicans want. The problem for Perry is that having spent the last decade as governor of Texas, his resume is somewhat thin on national security credentials; and, if he uses his work to secure the border to prove his bona fides, he runs the risk of inviting attacks on his more moderate immigration positions.

* Passing the “commander-in-chief” test: President Obama’s biggest strength heading into the 2012 election will be on national security and foreign policy issues where he has not only made good on his big campaign promise (the drawdown of troops in Iraq) but also played a major role in the deaths of both Osama bin-Laden and Moammar Gaddafi.

While national security isn’t likely to be a top-of-mind issue for most voters, a confidence in a person’s ability to keep the country safe and represent it on the world stage is a major intangible that goes into a voter’s decision.

Republican voters will undoubtedly be casting forward to a debate between the men and woman on the stage tonight and President Barack Obama next fall. Given that, the candidates have to show themselves ready, willing and able to assume the heavy responsibilities of being the commander-in-chief.

* A more measured Ron Paul? Probably not: In many areas — distrust of the Fed, scorn for the growing size of government — the Texas Republican Congressman finds himself very much in line with the mainstream of the Republican Party.

But on matters of national security and foreign policy, Paul is decidedly outside of that mainstream. He has suggested that America’s approach to foreign policy played a role in the terrorist attacks of Sept. 11, 2011 and believes strongly that the U.S. must get its troops out of foreign countries.

While those views light up Paul’s base, they do nothing to expand his coalition. And, if Paul wants to actually have a shot at winning the Iowa caucuses and being a major factor beyond that, he has to find a way to grow beyond the Paul-ites who will do anything for him.

So, will Paul temper any of his less-mainstream views on national security/foreign policy tonight? Our guess is “no”, but it would be a smart strategy if he would.

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