By David Henry TAMPA, Florida (Reuters) - As final ballots come in on a proposal to strip JPMorgan Chase & Co Chairman and Chief Executive Jamie Dimon of his chairman title, some worry about what will happen if shareholders win what will likely be a close vote. JPMorgan's annual meeting on Tuesday will bring to head a months-long and bitter shareholder campaign demanding more oversight of Dimon, who has suggested that he may eventually leave the bank if he loses the vote. Investors say that while Dimon, 57, may need more oversight after the bank posted $6. ...