WASHINGTON (Reuters) – The U.S. House of Representatives on Thursday failed to overturn President George W. Bush’s veto of a plan to expand a popular children’s health care program and pay for it by raising tobacco taxes.

The 273-156 vote fell short of the two-thirds needed to overturn a presidential veto, giving Bush a major legislative victory but one that Democrats are likely to use against his Republicans in the 2008 elections.

Democrats, who control Congress, vowed to continue pushing for the expanded program, which would provide health care to about 10 million children in low income families.

"In the coming days, Democrats will not back down and we will insist on providing health care coverage to these 10 million children," said Rep. Rahm Emanuel, an Illinois Democrat.

The battle over the program, which provides health coverage to children of families unable to afford insurance but who earn too much to qualify for the Medicaid health care program for the poor, has been intense.

"The president is deluding himself if he doesn’t think this veto will hurt millions of children," said Rep. Frank Pallone, a New Jersey Democrat.

Bush said the legislation, which would raise funding for the program to $60 billion over five years from the current $25 billion level, goes too far and was a major step toward government-controlled health care.

The bill represented a compromise between Democrats and a group of Senate Republicans who argued that the extra $35 billion was needed to ensure coverage for more eligible children. Currently about 6.6 million children are covered by the program, which enjoys broad support among health groups and state governors.

Health care is becoming a major issue in campaigns for next year’s presidential election and Republicans who voted with Bush have been pummeled by television and radio ads sponsored by unions and liberal advocacy groups.

Bush asked for just $5 billion in extra funding over five years, a figure that backers of the programs say is not enough to cover the current number enrolled.

Bush, who is now talking about a compromise, suggested on Wednesday that he would be willing to provide enough money to ensure coverage for an additional 500,000 children who are eligible, but not currently enrolled in the program, far below the 3.4 million more kids Democrats want to cover.