WASHINGTON (Reuters) - The House of Representatives was poised to vote on a $700 billion bailout package for U.S. banks, under pressure from all sides as the effort to head off a spreading financial crisis hung in the balance.

Following is a rundown of the changes to the original bill, along with some of the options that the Treasury, Federal Reserve and other agencies could employ to calm markets if the plan is rejected a second time.

REVISIONS TO THE $700 BILLION ASSET RESCUE PLAN

* The bill would raise the Federal Deposit Insurance Corp's current insurance limit to $250,000 per account from $100,000. The FDIC also would receive temporary unlimited borrowing authority from the Treasury under the bill. The measure is intended to boost banking system confidence and could be well-received in wealthier Republican congressional districts.

* Some 24 million middle-class taxpayers would get relief from a one-year fix that shields them from higher tax rates under the Alternative Minimum Tax. The issue comes up every year and temporary fixes routinely win broad support in Congress.

* It extends tax deductions for state and local sales taxes and allows deductions for state and local property taxes and higher education expenses for taxpayers who do not itemize their tax returns.

* The bill includes $18 billion in tax breaks for clean and renewable energy by continuing production tax credits for wind and refined coal, as well as breaks for solar and plug-in electric vehicles.

* The bill includes extension of favorable business tax provisions, such as tax credits related to new markets and research and development as well as the tax treatment of costs for retail and restaurant improvements.

* The bill would require insurance plans that offer mental health benefits to offer them at the same level as medical-surgical benefits.

* It includes various other provisions in apparent bids to secure specific votes. Among these are an exemption for excise taxes on certain wooden arrows designed for use by children and more favorable tax treatment of income from litigation over the 1989 Exxon Valdez oil spill in Alaska. The arrow provision would aid a company in southwestern Oregon, represented by Democrat Peter DeFazio, who voted no on Monday. The Exxon Valdez provision is aimed squarely at Rep. Don Young, an Alaska Republican who also voted against the bill on Monday.

* The bill also gives the Securities and Exchange Commission authority to suspend "mark-to-market" accounting standards to protect investors and the public interest. It also authorizes a study on the advisability of modifications to the practice, which has been blamed for billions of dollars of write-downs by financial services firms, eroding their balance sheets, as they struggle with elusive valuations in an illiquid market.

* Some of the provisions could imperil votes of Democrats who voted "yes" on Monday. Democrats previously stalled a Senate-approved bill that contained the energy and business tax breaks because of disagreements on how to pay for them.

OPTIONS FOR FED, TREASURY, REGULATORS IF BILL IS REJECTED

* The Federal Reserve could cut interest rates further to try to stave off a deep recession. Its next meeting is October 28-29, but it could announce an emergency cut before then, perhaps in conjunction with other central banks. However, some policy-makers remain concerned about inflation, and with overnight rates already at a low 2 percent, the Fed has limited capacity for further cuts. In addition, banks saddled with bad assets may still be unwilling to lend even if rates were lower.

* The Fed will likely continue to flood credit markets with liquidity. On Monday, it dramatically increased its term loan auction capacity to $300 billion and set-up a new $150 billion loan facility for year-end. That's in addition to lending at its discount window, which hit a record $187.75 billion in the week ended September 24. In addition, the Fed is providing up to $620 billion in U.S. dollars to other central banks.

* The Treasury and the Federal Deposit Insurance Corp can continue to arrange case-by-case rescues and mergers between distressed financial institutions. Thus far, however, these actions have not restored confidence in the financial system.

* In particular, the FDIC can waive a requirement that it pursue the least-costly solution to a bank failure when it is determined there is a systemic risk, as it did the sale of Wachovia Corp's banking operations to Citigroup.

* McCain has suggested the Treasury use its existing authorities to help stem the crisis, including broadening use of the Exchange Stabilization Fund. The Treasury has already tapped the $50 billion fund to guarantee money market mutual funds, so any remaining capacity is limited.

* The Treasury could invest capital into mortgage finance companies Fannie Mae and Freddie Mac and use these institutions to purchase distressed mortgage-related debt, according to some analysts. When they were placed under a federal conservatorship in early September, the Treasury said the companies would purchase an initial $10 billion in mortgage-backed securities.

* The Securities and Exchange Commission could extend its emergency ban on short selling of more than 900 financial services stocks for the maximum 30 days. The emergency order is set to expire October 2.

* The SEC could suspend or amend mark-to-market accounting standards, which have been blamed for the deteriorating asset values on financial services firms' balance sheets.

(Reporting by David Lawder, Donna Smith, Ayesha Rascoe, Richard Cowan and John Poirier; Editing by Chizu Nomiyama)