WASHINGTON -- Republicans held a commanding edge in elections for the House of Representatives on Tuesday, capitalizing on dissatisfaction with President Barack Obama and national malaise to push their numbers toward the highest levels in 65 years.

The Republicans had won more than 170 seats as polls closed in the East and Midwest and were certain to surpass the 218 needed for a majority if incumbents prevailed as expected in the West.

The president's party typically loses seats in the elections between presidential ones, but Obama's low approval ratings around 40 per cent have been a drag on fellow Democrats, along with public unease with the Islamic State group threat, the Ebola outbreak and a lacklustre recovery from the 2008 recession.

Evan Jenkins, a Democrat-turned-Republican state senator in West Virginia, knocked out 19-term Rep. Nick Rahall, one of the last white Democrats in the South. Republican Rick Allen prevailed over another Southern Democrat, five-term Rep. John Barrow of Georgia.

Another winner was Dave Brat, a professor who had a surprise upset of Republican Majority Leader Eric Cantor in a June primary.

Republicans also won the seat of a retiring Democrat Mike McIntyre in North Carolina, knocked out Democrat Joe Garcia in Florida and eased out a freshman Democrat Bill Enyart in Illinois. Republican challengers had the edge in Democratic seats in Maine, New Hampshire, New York and Texas, as well as another seat in Illinois.

Some two dozen Democratic incumbents had been in jeopardy, but just a handful of Republicans faced competitive races. Republican victories in the last such elections in 2010, fueled by the rise of the ultra-conservative tea party, gave the party the advantage in redrawing congressional districts.

The Republicans were likely to match the 246 House seats of 1947-1949 when another Democrat, Harry S. Truman, occupied the White House. Democrats still hold the modern-day edge for most seats -- 292 -- in 1979.

A solid Republican majority means Speaker John Boehner, who was on the ballot for a 13th term, can afford defections from his increasingly conservative caucus and still get legislation passed. Republicans are counting on partnering with a Republican-led Senate.

Boehner raised $102 million to ensure that Republicans would tighten their grip on the House.

Obama, whose party lost 63 seats in 2010, would become the two-term president with the most midterm defeats, surpassing Truman's 74.

All 435 House seats were on the ballot Tuesday, but the roster of competitive races was less than 10 per cent of those.

- Associated Press writers Donna Cassata, Erica Werner and Andrew Taylor contributed to this report.