WASHINGTON (AP) - Democratic leaders in Congress have sent President Bush a veto-proof bill to authorize spending $23 billion in water projects, having waited more than a month to request his signature on a measure he has threatened to veto.

Democrats have more than the two-thirds majority votes in both chambers of Congress needed to override Bush if he vetoes the bill. The Senate passed it on Sept. 24 by a vote of 81-12; the House passed it Aug. 1 by a vote of 381-40.

An override would mark the first such loss for Bush and could cast him in a more politically vulnerable light.

“This congressionally approved bill authorizes more than 200 projects to protect lives and livelihoods in our communities from the devastating impacts of flooding by building and repairing floodwalls and levees, as well as by restoring wetlands that absorbfloodwaters, House Speaker NancyPelosi, D-Calif., and four other top House Democrats wrote Bush in a letter Friday urging him to sign the bill they sent to him on Tuesday.

The bill funds work to restore the hurricane-ravaged Louisiana coast and Florida's Everglades, projects the Bush administration supports. But the president threatened a veto after the bill's anticipated cost ballooned by $9 billion as projects were added in negotiations between the House and Senate.

The legislation authorizes $3.6 billion for major wetlands and other coastal restoration, flood control and dredging projects for Louisiana, a state where coastal erosion and storms have resulted in the disappearance of huge areas of land.

Sen. James Inhofe, R-Okla., among the Republicans who usually side with the president, has said that Bush “knows it's going to be overridden.

Despite such odds, Democrats held onto the bill for a month. Overriding Bush would give Democrats an ace to play after failing to add a single Republican vote in a separate bid for a veto-proof margin on a children's health bill, a version of which Bush has already vetoed.