A Republican redistricting of Texas and the advantage of incumbency virtually assure that Republicans will continue to run the House in 2005 but large numbers of new voters and a heavy turnout could still produce some surprises Tuesday.

Early, absentee, military and provisional votes — always hard to predict — also add uncertainty to several races.

All 435 seats in the House are up for grabs but only about three dozen are considered competitive. Democrats hold 205 seats and have the support of House's lone independent, Bernie Sanders (search) of Vermont, so would need a net gain of 12 to take control.

Statistically they could do it, but only if John Kerry (search) produces a tide of new voters, including those angry over the 2000 presidential race.

"We can lose a couple of incumbents and still, if we have some momentum with the open GOP seats and the Republican-held seats where we have great challengers, we can take the House back," said California Rep. Robert Matsui (search), head of the Democratic Congressional Campaign Committee.

Weirder things have happened. Republicans picked up 54 House seats in 1994 to take control of the House for the first time in four decades. But they're confident they won't lose it now.

Ballot initiatives in 11 states against gay marriage and President Bush's popularity in the South and parts of the West are expected to produce a large turnout of social conservatives who are a big part of the GOP's base.

Add to that the loss of up to six Democratic seats in Texas in a redrawing of districts engineered by House Minority Leader Tom DeLay, and Republicans are confident they'll hold their own if not gain seats.

"As I see it, the Democrats lose several incumbents come Nov. 2," said Rep. Tom Reynolds, R-N.Y., head of the House GOP campaign organization.

Some races that were supposed to be blowouts moved closer in the waning hours.

In Kansas City, Mo., Mayor Emanuel Cleaver was the heavy favorite to succeed retiring Democratic Rep. Karen McCarthy. But the race tightened after Republican candidate Jeanne Patterson poured nearly $3 million of her own money into TV ads questioning Cleaver's ethics.

Rep. Christopher Shays, R-Conn., has been comfortably re-elected since 1987. But his work with Democrats on campaign finance reform and trying to get the Sept. 11 commission's recommendations into law has turned off some Republicans. Polls now show him under 50 percent with Democrat Diane Farrell in what normally is a safe GOP district.

Turnout for Bush and Kerry could decide two House races in Pennsylvania, where Sen. Arlen Specter's bid for a fifth term produced two vacant seats: in the 15th district when Rep. Pat Toomey challenged him in the GOP primary, and the 13th district seat held by his Democratic challenger, Rep. Joseph Hoeffel.

An October AP analysis of the most up-to-date figures from across the country found that, in every state where complete data is available, the Democrats have registered more new voters than Republicans.

In Texas, where Republicans used redistricting to make re-election harder for Democrats, a high turnout could help some of those Democrats survive, Matsui said.

The nation's most expensive House race has 13-term Democratic Rep. Martin Frost pitted against Republican Rep. Pete Sessions, a four-term veteran, in a new GOP-leaning district. As of mid-October, Frost has spent $3.9 million and Sessions about $2.7 million.

Last year's redistricting in Texas has already turned one seat over to Republicans. After spending 23 years in the House as a Democrat, Ralph Hall switched to the Republican side in January. And four-term Democrat Jim Turner decided against seeking another term after he was put into a new district dominated by Republicans.

In other Texas races Democratic Rep. Charles Stenholm, a 13-term veteran, is fighting for his political life against freshman GOP Rep. Randy Neugebauer in a district in which two-thirds of the voters are new to Stenholm.

Democratic Texas Reps. Max Sandlin, Nick Lampson and Chet Edwards also face difficult fights. Republicans give only Edwards a shot at keeping his seat.