A corrected version of the story appears below.

NEW YORK (AP) -- Jumbo mortgage lender and real estate investment trust Thornburg Mortgage Inc. could collapse if a vote to increase the number of outstanding shares is delayed or fails, the company said in a letter to shareholders.

The letter, dated Tuesday, was submitted to the Securities and Exchange Commission as part of a regulatory filing Wednesday.

The vote to increase the number of common shares outstanding is required as part of a capital raising plan Thornburg formalized earlier this week that would allow the company to pay off its margin calls and repurchase agreements.

Thornburg is raising $1.35 billion through the sale of senior subordinated secured notes that also come with options to purchase shares of common stock for 1 cent per share.

If the vote is approved, existing common shareholders would own only about 5.5 percent of the common stock.

A failure to complete the raising of new capital would "seriously jeopardize the financial viability of the company," Larry Goldstone, the company's president and chief executive, wrote in the letter.

Therefore, Thornburg's audit committee members, via an exception in the New York Stock Exchange's shareholder approval policy, have decided to not seek stockholder approval for the move.

In early March, Thornburg disclosed it has faced nearly $1.8 billion in margin calls since the beginning of the year. The lender said it was unable to meet $610 million in calls, which led it to look for new ways to raise capital. If it raises the capital, Thornburg would also receive a one-year reprieve from facing any future margin calls.

Thornburg faced a similar round of margin calls in August, but was able to meet them.