As a management consultant recently observed, if many U.S. banks were hospital patients, they would no longer be classified as in critical condition but still wouldn’t be considered quite well enough for discharge.

That observation was prompted by a June study of Federal Reserve data on almost 7,000 U.S. banks. The study, conducted by Institutional Risk Analytics, a research firm, concluded that the number of financially troubled banks is rising. The firm gave a failing grade for financial soundness to about 25% of the banks, or 1,882 banks, to be exact. In contrast, three months earlier, the percentage of financially troubled banks was 17%.

For our part, we noted that the financial woe seemed especially acute among regional banks, 75% of whom reported losses in their most recent quarter. Alas, we think regional banks’ problems are likely to be further compounded over the next few years by increased delinquencies on commercial real-estate loans, which appear to be the next financial bullet to be dodged. One can only conclude that the financial crisis that began with subprime mortgages in late 2007 may be unwinding, but it’s by no means over just yet.

In a still-precarious financial-services environment, the regional banks that are likely to do best going forward are those with strong balance sheets and capital ratios and ample loan-loss reserves, in our estimation. We think six regional banks in particular -- Bank of Hawaii, Bank of the Ozarks, Comerica, Fifth Third Bancorp, Prosperity Bancshares, and Western Alliance Bancorporation -- possess precisely those financial characteristics. As a result they should be positioned advantageously to increase their earnings and market shares over the next few years.

For instance, one balance-sheet metric that we think reflects their well-fortified capital position is the tangible common equity/tangible assets (TCE/TA) ratio. As we see it, the TCE/TA ratio is not only a good indicator of their ability to absorb future losses but also their ability to expand the balance sheet by gaining new business at profitable margins. In short, it’s a good metric for gauging a bank’s prospective earnings power. And significantly, as of the second quarter, the TCE/TA ratios for Bank of Hawaii, Bank of the Ozarks, Comerica, Fifth Third Bancorp, Prosperity Bancshares, and Western Alliance Bancorporation were all commendably high, with a median of 7.2%, according to Keefe, Bruyette & Woods, an investment bank.

In addition, those six banks in aggregate have raised their loan-loss reserves to what we think are prudent levels, to higher levels than those of most of their peers. In August The Wall Street Journal reported that the banking industry’s ratio of reserves to bad loans was 63.5%, the lowest level since 1991. In comparison, the median ratio for these six regional banks is 86.8%.

As we see it, the balance-sheet strength of Bank of Hawaii, Bank of the Ozarks, Comerica, Fifth Third Bancorp, Prosperity Bancshares, and Western Alliance Bancorporation should prove critical in helping them bolster their now-depressed earnings as the economy recovers (which we think is happening now) and the cycle of loan charge-offs peaks (which we think may happen in 2010).

What’s more, in an industry that’s now exceptionally ripe for consolidation, being well-capitalized means that the six banks can acquire smaller, financially stretched banks at attractive prices and in the process expand their franchises and market shares.

To be sure, there’s likely to be no shortage of candidates for acquisition, especially under Federal Deposit Insurance Corporation-assisted deals. In August the Federal Reserve increased the number of banks on its "problem list" to 416, up from 117 in June 2008. More than 70 banks have failed so far this year, by The New York Times’ count. A recent high-profile fatality was Chicago’s Corus Bankshares, an institution with about $4 billion in assets that the Times characterized as "the most aggressive financier of condominium-construction loans during the real-estate boom." Our contacts in the industry estimate that several hundred regional and community banks (out of about 8,000 nationally) may meet Corus’ fate and become insolvent. And they speculate that at least a few hundred more banks may be so impaired financially that they become acquisition prey -- wounded gazelles that may be stalked by our six regional-banking lions and others.

Here are brief profiles of the six:

*  Bank of Hawaii (assets: about $10.8 billion, market capitalization: about $2 billion, headquarters: Honolulu) competes in Hawaii (obviously) as well as in American Samoa and the Pacific Islands, that vast chain of more than 20,000 islands in the South Pacific that includes Melanesia, Micronesia, and Polynesia. The bank has steadily increased its earnings per share over the past five years. Its ratio of reserves to bad loans is the highest among the six banks, at 856%.

*  The service area of Bank of the Ozarks (assets: about $3 billion, market capitalization: about $420 million, headquarters: Little Rock) is composed of Arkansas, Texas, and North Carolina. In that service area Bank of the Ozarks has generated a compound annual growth rate in diluted earnings per share of 19% over the past 10 years. The bank’s net charge-off ratio, a measure of asset quality, is less than 0.5%, compared with an average of more than 1% for all banks. Its ratio of reserves to bad loans is 244%.

*  Comerica (assets: about $63 billion, market capitalization: about $4 billion, headquarters: Dallas) has done well despite serving what have been some of the most economically distressed domestic markets recently: Texas, Arizona, California, Florida, and Michigan. In the second quarter the bank boosted its already strong capital ratios, which we think should enhance its margin of operating safety in coping with the financial crisis. Its TCE/TA ratio is 7.6%.

*  Fifth Third Bancorp (assets: about $116 billion, market capitalization: about $8.5 billion, headquarters: Cincinnati) does business in 12 states in the Midwest and South. Like the five other banks, Fifth Third has adjusted its loan-loss reserves upwards but has done so to a greater extent: it has more than doubled its reserve ratios from 1.85% last year to 4.28% in the second quarter. (The average reserves for all banks are now 3.1%, Goldman Sachs estimates. In past troughs of the credit cycle, reserves have typically reached about 4%.)

*  Prosperity Bancshares (assets: about $9 billion, market capitalization: about $1.6 billion, headquarters: Houston) has offices throughout much of Texas, including the major metropolitan areas. As befits its name, Prosperity has been consistently profitable, even during the oil-industry slump of the late 1980s that hobbled the Texas economy. In an effort to help protect its future profitability from rising charge-offs on commercial real-estate loans, Prosperity in the second quarter increased its provision for credit losses to $6.9 million, up from $1 million a year earlier.

*  Western Alliance Bancorporation (assets: about $5 billion, market capitalization: about $500 million, headquarters: Las Vegas) operates in Nevada, Arizona, Colorado, and California under various financial-services brands. The bank’s TCE/TA ratio is 7.8%. The recent recipient of $420 million from the Treasury Department’s Troubled Asset Relief Program and an equity offering, Western Alliance, as an FDIC-approved bidder for failed or troubled banks, has the means to pursue what promises to be a glut of acquisition opportunities in its markets, in our view.

In conclusion, we consider these six regional banks, unlike many of their peers, as well capitalized and well reserved. That’s a distinct competitive advantage in a financial marketplace that shows evidence of remaining somewhat unwell.