Here's a brutally honest (Oh boy, am I going to get a lot of angry emails) breakdown of all five of the top tier contenders (Full disclosure: I was a consultant for the Duncan Hunter campaign and he's still my favorite candidate).
John McCain: Johnny Mac is a fiscal conservative, has a lot of experience, particularly on foreign policy, has a strong pro-life voting record, and he polls very well. This is a man who can win over independent voters and therefore, is capable of beating Hillary Clinton.
However, the New York Times’ favorite Republican has made a career out of breaking conservative hearts on everything from campaign finance reform to immigration, to taxes, to judges, to enhanced interrogation techniques. It's a pattern that has been repeated again and again. A huge issue for conservatives comes up and then McCain leads a group of squishy Republicans who very publicly side with the Democrats. In return, McCain gets to bask in waves of positive attention from the mainstream media, which lauds him as a straight-talking maverick in return for his betrayal of conservative principles.
That's why John McCain is loathed by so many grassroots conservatives and it's why he would be extremely frustrating to conservatives if he made it into the White House. Moreover, it's entirely possible that his excellent polling numbers which are based on the great press he receives, would evaporate along with all his positive coverage once he became the GOP nominee -- instead of the Republican in the Senate most likely to side with Democrats. So, even his solid poll numbers that appear to show he’s electable are far from a sure thing.
Mike Huckabee: Despite what some people are claiming, Huckabee would be a fun guy to run against Hillary. That's not just because he would drive the Christian-hating netroots crazy, but because you just have to think that a former pastor who's the most charismatic, likable candidate in the race, would almost have to do well against the cold, corrupt, wicked witch of New York. Trust me; if it all boiled down to Huckabee and Hillary, no one would have a hard time trying to figure out an answer to the classic, "Which candidate would you most like to go to a ballgame with," question. Heck, even Bill would probably choose Huckabee if he thought his wife wouldn't find out about it.
On the other hand, although Huckabee is rock solid on social conservative issues, balanced the budget in Arkansas, and has abandoned his pro-amnesty stance for a great new plan to deal with illegal immigration, he comes across as a big government Republican, an enemy of free trade, a tax hiker, a nannystater, and more than a little bit of a ditz on foreign policy issues. In other words, if after two terms of George Bush, you're sick and tired of hearing the words "compassionate conservatism," this is not the guy for you.
Moreover, his biggest strength also may be his biggest weakness. Huckabee is a former pastor and sometimes, when you listen to him, you start to wonder if has taken a little bit too much of the mentality of his former profession into his current one. Just to name a couple of examples, he seems to have been far too lenient with illegal aliens and criminals when he was governor of Arkansas. Put another way, I really like my pastor, but I'm not sure he'd be hard enough to deal with Iran, Al-Qaeda, or illegal aliens. I have those very same doubts about Mike Huckabee.
Rudy Giuliani: As you've no doubt heard from the man himself if you've watched any of the debates, Rudy has a great record of fiscal conservatism and did a phenomenal job of dealing with crime when he was Mayor of New York. He's also charismatic and has gotten a lot of credit, deservedly so, for his great leadership in the aftermath of 9/11.
However, if Rudy had been anywhere other than ultra-liberal New York, given his positions on the issues, he probably would have been a blue dog Democrat instead of a Republican. Rudy is not a conservative and he would not make conservatives happy if he actually got in the White House. That's true of conservatives in general and doubly true of social conservatives, who would undoubtedly stay home by the millions rather than vote for a pro-abortion candidate who has had multiple affairs and associates with the shadiest cast of characters this side of the Clintons.
That brings us to what's supposed to be Rudy's greatest strength: his electability. While you might think that a moderate, generally well liked New York Republican would put all sorts of blue states into play, the head-to-head polling that has been done so far doesn't bear that out. At the moment, Rudy isn't beating Hillary Clinton in a single state that George Bush didn't win in 2004. Moreover, it's John McCain, not Rudy, who has consistently had the best head-to-head numbers nationally against the Democrats. Since Giuliani isn't a conservative, if you take away the electability angle, what's left that makes him worth voting for?
Fred Thompson: "The Fred" is a peculiar case. He is a consistent, movement conservative whose views match up better with those of the base than any of the other top tier candidates. He's a fiscal conservative, a federalist, a man with a perfect pro-life voting record, and all the right positions on illegal immigration. He is also, by far, the most popular candidate with conservatives online, quick on his feet, has a good sense of humor, comes across as presidential, and more than any other Republican running, he has put out serious, detailed policy plans. Judging by that, you'd think he'd be dominating the field. So, why isn't he?
Simple: Because he got in the race too late.
Initially, it may have seemed like a smart move to wait to jump in because Fred's poll numbers kept going up. But eventually, expectations became so sky high that no one could have lived up to them. So, when Fred got in the race, he was almost destined to disappoint people -- and he did. Fred and his campaign took about a month to get their sea legs, but unlike the other campaigns that had their growing pains at the start of the year when no one was paying attention, the Thompson campaign was under the microscope and being examined by people who were practically expecting him to be Reagan reincarnated. Meanwhile, many of the people in the conservative press savaged Fred mercilessly because they had already picked out a candidate to back before he ever got in the race and so they never saw him as anything other than an impediment to "their guy's" chances of winning. Today, Thompson's campaign is well run, he's working as hard as the other top tier candidates, he has proven to be an excellent debater, and he's still probably the only top tier candidate who has the potential to give the majority of Republicans someone they'd like to vote for, as opposed to someone they'd only vote for out of fear of a Hillary Clinton presidency. However, despite all that, he still has yet to get out from under the shadow of the negative first impression that was left with people when he first entered the race.
Mitt Romney: At first glance, Mitt, who has become the de facto Republican establishment pick since McCain tanked, looks like a good candidate. He has charisma, he looks presidential, he has a solid business background, he's run a great campaign, he can raise money, and he doesn't seem to have a lot of baggage. He also says all the things that conservatives want to hear about illegal immigration, spending, and foreign policy.
However, he has three major league problems.
The first, which has been discussed ad nauseum during the campaign, is his religion. It turns out that roughly 18% to 24% of the population already says that they won't vote for a Mormon and that number is likely to increase if Mitt gets the nomination as the mainstream media spends a whole year trying to convince the American public that Mormons are weird, racist polygamists, who all wear magic underwear and are looking forward to increasing their numbers exponentially once one of their own becomes President. If you winced reading that or thought it was unfair, just imagine what it would be like seeing it for a year straight on the evening news and in your local paper if Mitt gets the nomination.
The second problem Mitt has is that he's a flip-flopper (Is it my imagination or didn't our party spend 2004 beating up on John Kerry for that?) who shifted his positions markedly to the right in an effort to make himself more palatable to the sort of rock ribbed conservatives who tend to vote in the GOP primaries. The reality is that the Mitt Romney who is running today does not hold the same positions as the Mitt Romney from a few years ago and if he won the nomination, the Mitt Romney who runs in the general election is probably not going to hold the same positions as the Mitt Romney you're hearing from today. In other words, Mitt isn't telling people what he believes, he's telling people what they want to hear, and that means if the polls change, his views will probably change as well if he thinks it's to his advantage.
For example, Mitt used to be pro-abortion, pro-illegal immigration, and ran to Ted Kennedy's left on "gay rights" issues. Now, he's anti-abortion, breathing fire on illegal immigration, and an ardent opponent of gay marriage. So, what positions would he hold if he wins the presidency? Since he doesn't seem to have many core beliefs, you almost have to think he'd simply follow the most politically expedient path.
Both of the two previous problems have led to Mitt's biggest problem, one which seldom seems to be discussed: he probably cannot beat Hillary Clinton in a general election. His head-to-head numbers against her in the states have been and remain terrible. Whether you like Mitt or not, having him as our nominee would be horribly depressing because it would likely mean that not only would we lose the presidency, we would spend all of 2008 knowing that we were going to lose. It would be like the 1996 campaign all over again with Mitt playing the part of Bob Dole, the guy who is way behind and generates no enthusiasm from the base, going up against a hated foe of conservatives that he isn't capable of defeating.