"In our view the top question on investors' minds will be how much capital does a bank need under precedence set by PNC ... and others in recent months," analysts at FBR Capital Markets said in a research note last week. The FBR note goes on to say that two schools of thought exist on how much capital is needed to be raised in order to repay TARP funds. The first requires banks to undergo a common equity raise equal to half the amount of outstanding TARP funds minus half of the capital released from any deleveraging or business divestments, FBR analysts say. Or it could be that regulators are gravitating that 8% common ratio, even though there have been exceptions, including Bank of America and U.S. Bancorp ( USB), according to the FBR analysts. SunTrust Banks ( STI), Regions Financial ( RF), KeyCorp ( KEY) and Fifth Third Bancorp ( FITB) all bolstered their balance sheets last May following the stress tests that found capital deficiencies. Yet the FBR analysts say these banks may have to raise extra capital if they want to repay the government's capital injections. " T he blueprint so far suggests that additional raises may be necessary at some point in the future," the note says. " E arnings and credit quality are not enough to get out of TARP," said FBR Capital analyst Bob Ramsey during a follow-up interview. "You absolutely do need to have strong capital levels." Ramsey covers banks primarily in the Northeast, which have held up typically better than banks located in harder hit areas of the country. But one bank under his coverage that may need to raise capital to repay TARP is M&T Bank ( MTB). "They are a healthy bank, but they do have thin capital," he says. As of Dec, 31, the relevant common equity ratios of some of the more prominent regionals that still have TARP tabs were 8.5% for Regions Financial, which owes $3.5 billion; 7.5% for KeyCorp, which owes $2.5 billion; 8.8% for SunTrust, which owes $2.5 billion; and 7% for Fifth Third, which owes $3.4 billion.