WASHINGTON — Democrats expanded their majority in the House with historic gains by dominating the Northeast and ousting Republicans in every region.

Their defeat of 22-year veteran Rep. Chris Shays in Connecticut gave Democrats every House seat from New England. Their victory in an open seat on New York's Staten Island gave them control of all of New York City's delegation in Washington for the first time in 35 years.

Democrats also rode the coattails of a decisive victory by Barack Obama in New Mexico to win one House seat they haven't controlled in four decades and another the GOP had held for 28 years. Both were left up-for-grabs by GOP retirements.

"The American people have called for a new direction. They have called for change in America," said House Speaker Nancy Pelosi, D-Calif.

Exit polls showed voters troubled by the battered economy and deeply dissatisfied with President Bush.

Democrats unseated 12 Republican incumbents and captured nine open GOP seats, capitalizing on the unusually high 29 Republican departures. Republicans were only able to knock off four Democratic incumbents.

With fewer than a dozen races undecided, Democrats had won 251 and were leading for another five. Republicans had won 171 and were leading in six. If those trends held, Democrats could have a net gain of 20 seats. And Republicans were on track for their smallest numbers since 1994, the year a Republican Revolution retook the House for the first time in 40 years.

The Democratic edge in the current Congress is 235-199 with one vacancy in a formerly Democratic seat. Two Louisiana seats, one Democratic and one Republican, won't be decided until December because hurricanes postponed their primaries until yesterday.

In the northeast, GOP Reps. John R. "Randy" Kuhl of New York and Phil English of Pennsylvania were defeated. Democrat Eric Massa unseated Kuhl in New York's southern tier, and Kathy Dahlkemper, a 50-year-old mother of five, toppled English in Pennsylvania's northwest corner.

In Connecticut, Democrat Jim Himes, a Greenwich businessman, defeated Shays despite the Republican's highly publicized late criticism of John McCain's presidential campaign.

Democrats also captured seats left up-for-grabs by GOP retirements. Former congressional staffer Dan Maffei won election to succeed retiring GOP Rep. Jim Walsh, becoming first Democrat in nearly 30 years to represent the district around Syracuse, N.Y.

Democratic city councilman Mike McMahon won the race on Staten Island to succeed GOP Rep. Vito Fossella, R-N.Y., who was forced to resign amid drunken-driving charges and revelations that he has a child from an extramarital affair.

In New Jersey, Democratic state Sen. John Adler won election to succeed retiring Rep. Jim Saxton, R-N.J.

In the South, too, Democrats made inroads. High school civics teacher Larry Kissell won election in North Carolina, defeating Republican Rep. Robin Hayes. Democrat Gerald Connolly, a former chairman of the Fairfax County Board of Supervisors, was elected to succeed retiring GOP Rep. Thomas M. Davis III in northern Virginia.

In Florida, GOP Rep. Tom Feeney — under fire for ties to disgraced lobbyist Jack Abramoff — lost to former state Rep. Suzanne Kosmas. To the east, Rep. Ric Keller, R-Fla., lost to Democratic attorney Alan Grayson in Orlando.

In Illinois, Democrat Debbie Halvorson, speaker of the state Senate, won election to a seat held by retiring GOP Rep. Jerry Weller.

The news wasn't all good for Democrats. Republican attorney Tom Rooney defeated first-term Democratic Rep. Tim Mahoney of Florida, who had admitted to two extramarital affairs just weeks before Election Day.

And Republican Bill Cassidy dealt Rep. Don Cazayoux, D-La., elected in a special election six months ago, a bruising defeat.