By Charles Babington THE ASSOCIATED PRESS WASHINGTON – The House voted Tuesday to expand health insurance for children, but the Democratic-led victory may prove short-lived because the margin was too small to override President Bush’s promised veto. Embarking on a health-care debate likely to animate the 2008 elections, the House voted 265-159 to expand the State Children’s Health Insurance Program, or SCHIP, by $35 billion over five years. Bush says he will veto the bill due to its cost, its reliance on a tobacco tax increase and its potential for replacing private insurance with government grants. After the vote, House Speaker Nancy Pelosi, D-Calif., said she was disappointed that Bush “has issued a veto threat against a bill that has so much bipartisan, indeed nonpartisan, support.”160Want local news?Sign up for the Localist and stay informed Something went wrong. Please try again.subscribeCongratulations! You’re all set! SCHIP is a state-federal program that provides coverage for 6.6 million children from families that live above the poverty level but have trouble affording private health insurance. The proposed expansion, backed by most governors and many health-advocacy groups, would add 4 million children to the rolls. The bill drew support from 45 House Republicans, many of them moderates who do not want to be depicted as indifferent to low-income children’s health needs when they seek re-election next year. But 151 Republicans sided with Bush, a move that Democrats see as a political blunder. It hardly matters that the expansion would be expensive or a step toward socialized health care, Rep. Charles Rangel, D-N.Y., said during the House debate. When lawmakers go home, he said, “the question is, were you with the kids or were you not?” To overturn a presidential veto, both chambers of Congress must produce two-thirds majorities. The 265 yes votes in the House are two dozen fewer than Democrats would need to override Bush’s veto, and House leaders expect few members to switch positions. The Senate appears poised to pass the SCHIP expansion by a large margin later this week, but a Senate bid to override a veto would be pointless if the House override effort falls short.