A big majority of Americans support having women fight in combat roles in the U.S. armed services, and more see improved than compromised military effectiveness as a result of the change, according to a new poll by The Washington Post and Pew Research Center.

Last week, the Obama administration opened up combat roles to women in the military, and fully 66 percent of all Americans back the idea. Most men and women alike support the idea, as do majorities across party lines.

Most of those in military households -- including veterans themselves -- see the policy shift as a "major change," and they too are largely supportive of the move.

The widespread support for allowing women to serve in close combat is not new -- it was also high in a 2011 Washington Post-ABC News poll -- but the across-the-board acceptance of the substance behind the policy shift gives its proponents a boost.

In the new Post-Pew poll, most Americans -- and most veterans -- see the policy change as improving career opportunities for women in the military. In parallel, few, just 15 percent, see the shift as undermining military readiness, something critics of the move envision.

About twice as many, 29 percent, see improved military effectiveness as a result of having women in combat roles. More, 49 percent, see no discernible change.  Among those who have served in the military, 30 percent see better military operations, and 19 percent see diminished capacity; again a plurality, 46 percent, anticipates no change.

Partisan differences emerge on the readiness question. Republicans tilt toward the view that says the change will worsen military effectiveness than aid it, while Democrats are far more apt to see an upside than a down. Still, pluralities of all partisan stripes say the change will not make much of a difference.

The Post-Pew poll was conducted Jan. 24 to 27 among a random national sample of 1,005 adults. The margin of sampling error for the full survey is plus- or minus-3.5 percentage points. Click here to see full results and interactive breakdowns.

Cohen is director of polling for Capital Insight, the independent polling group of Washington Post Media. Clement is a pollster with Capital Insight.