The right has moved further right and the left has moved further left, poll shows

WASHINGTON (Reuters) - Americans are more divided along political lines than at any time in two decades, with about one in five defining themselves as consistently liberal or conservative, a poll showed on Thursday.

The hardening of ideological positions also means that more Americans are less likely to favor political compromise, the survey by the Pew Research Center for the People and the Press said.

"Liberals and conservatives disagree over where they want to live, the kind of people they want to live around and even whom they would welcome into their families," it said.

Polarization has come into sharp focus this week with the primary election defeat of Eric Cantor, the No. 2 Republican in the House of Representatives, by political novice David Brat, who had strong support from the conservative Tea Party movement.

The poll, the largest undertaken by Pew on U.S. political attitudes, showed that the share of Americans who express consistently liberal or consistently conservative views on political issues had doubled to 21 percent from 10 percent in 1994.

The leftward shift among Democrats has occurred gradually over the last 20 years. It has been driven by the liberalizing trend on such issues as homosexuality and immigration.

The shift among Republicans has become more pronounced in the last 10 years, the poll said.

For 49 percent of Americans, the preferred outcome in battles between congressional Republicans and Democratic President Barack Obama is to split the difference, with each side getting half of what it wanted, the survey said.

But consistent liberals on average say Obama should get two-thirds of what he wants, and consistent conservatives say congressional Republicans should get two-thirds of what they want.

Among both Republicans and Democrats, those who feel very unfavorably toward the opposing party are more likely than those with less intense views to say they make political donations, contact elected officials and say they always vote, it said.

The Pew poll was based on telephone interviews of 10,013 adults from Jan. 23 to March 16. It has a margin of error of 1.1 percentage points.

(Reporting by Ian Simpson; Editing by Eric Beech)