The Senate is expected to vote before its Columbus Day recess on legislation to raise the ceiling on the national debt to almost $10 trillion.

Sen. Tom Coburn, R-Okla., said Thursday he will force a roll-call vote on raising the debt limit. Treasury Secretary Henry M. Paulson Jr., told congressional leaders in a letter dated Sept. 19 that the statutory limit of $8.965 trillion would be reached Oct. 1. In a July letter, he had estimated that would occur in “early October.”

On Sept. 12 the Senate Finance Committee approved legislation (H J Res 43) to boost the debt limit by $850 billion, to $9.815 trillion. The House passed that measure automatically, without a roll call vote, when Congress adopted the fiscal 2008 budget resolution (S Con Res 21) earlier this year. But the Senate has no similar rule for automatic action.

No Senate vote has been scheduled yet, but one is expected soon.

The debt limit has grown by $3 trillion since 2002.

Debt that is subject to the statutory limit includes publicly traded securities purchased by Wall Street investors, savings bonds and special securities held by trust fund accounts that finance Social Security, Medicare and other government programs. If the debt limit is not increased, Treasury would be unable to pay interest on existing notes and bonds or borrow more funds.