Republicans certainly are justified in taking an optimistic view about the midterm elections in November. Even analyst Charlie Cook thinks they are likely to win the House and the Intrade betting odds have now moved in favor of a Republican majority in the House. And the Senate races continue to look good, with a likely Republican pickup of about 6 seats, and perhaps more.

Nevertheless, the GOP has one very substantial problem in the long term - an apparent weak bench of potential presidential candidates in 2012.

Probably the current frontrunner is former Massachusetts governor Mitt Romney. Mr. Romney has a business background and an understanding of economics, has won in a typically Democratic state and has improved his stump speech since his 2008 run. But there are a number of negatives, apart from unfair attempts to make his Mormon faith an issue. While governor of Massachusetts, Mr. Romney helped to enact the state’s Masscare health plan. This system seems pretty much indistinguishable from President Obama’s health care plan that is so unpopular with Republicans and many other voters. He will be at great pains to make the case that the systems are different. In addition, Mr. Romney was a well financed candidate in 2008 but he never seemed to connect with average voters. Maybe he will do considerably better this time, maybe not.

Another top tier candidate is likely to be former Arkansas governor Mike Huckabee. Mr. Huckabee is a likeable man, an ordained minister with an inspiring story of weight loss (who couldn’t respect someone who shed 100 pounds and ran marathons?) and a good sense of humor. He has done well on his Fox News television show. The big problem for Mr. Huckabee is appealing to voter bases outside rural areas and the South.

And, of course, there is Sarah Palin, the former Alaska governor and 2008 vice presidential candidate. An undeniably charismatic figure with a good (if brief) record as governor of Alaska, she certainly shook up the 2008 campaign. To many people she was a breath of fresh air. But to too many others (including not a few Republicans), she simply was not qualified, and perhaps not smart enough, for high office. Still a young woman in her mid-40’s, Ms. Palin may well be able to hone her image in the years to come. But her nomination for President in 2012 is a very big gamble.

But if not a high profile candidate like Mr. Romney, Mr.Huckabee or Ms. Palin, then who? General David Patraeus might make a strong candidate, but his recent appointment as commander in Afghanistan makes his availability questionable. There are a few experienced Republican governors around the country -Tim Pawlenty of Minnesota, Mitch Daniels of Indiana and Rick Perry of Texas - but none are exactly household names. Former House speaker Newt Gingrich has hinted that he might be interested, but he is a quite controversial figure. Senator Scott Brown of Massachusetts is a dynamic figure but he has just now been elected to federal office. Governor Chris Christie has done a great job in turning New Jersey around, but he has only been on the job for a few months. If she wins in her race for California governor in the fall, Meg Whitman may get some consideration on the base of her business experience, but again her governmental service will be very limited.

Sometimes a “nobody” candidate wins if there is enough dissatisfaction (see Warren Harding in 1920), but finding a suitable candidate against President Obama may prove to be a difficult task indeed.