A new survey by the Pew Research Center finds that a comfortable majority of Americans support keeping abortion legal -- posing a challenge for Republicans pushing aggressive measures aimed at curtailing abortion rights.

Fifty-four percent of the public supports legal abortion in all or most cases, while 42 percent believe it should be illegal in all or most cases, the poll found. The figures reflect a rise in support for abortion rights over the last two years.

In 2009, the same Pew survey found the general public much more evenly divided, supporting abortion rights by a margin of 46 to 44 percent. Last summer, the gap was 50 to 44 percent in favor of legal abortion.

Polling by Gallup found in 2009 and 2010 that a plurality, if not a majority, of Americans considered themselves "pro-life" as opposed to "pro-choice." Gallup last year labeled pro-life "the new normal" on abortion.

In the new Pew survey, Americans were predictably split on the issue along party lines, but independents said they support legal abortion by a remarkable 20-point margin (58 to 38 percent).

Upon taking control of the House in January, Republicans have made it a high priority to curtail abortion rights, primarily by advancing HR 3, "The No Taxpayer Funding For Abortion Act."

The sweeping measure, approved last week by the Judiciary Committee, expands the Hyde Amendment by eliminating employer or individuals tax deductions for any insurance plan that covers abortion -- even if it carrying the pregnancy to term may harm their health. The House has also voted to defund Planned Parenthood, one of the largest providers of women's reproductive health-care.