White House spokeswoman Jessica Santillo defended the law. "With more than 6 million people already signed up, and tens of millions gaining new protections, it's clear the law is working very well, despite coming under more attacks than any law in recent memory," she said in a statement.

Republican alternative

McMorris Rodgers, the fourth-ranking Republican in the House, said Republicans are developing a plan that would replace the president's signature law, which they've voted more than 50 times to repeal or revise since retaking the House in 2011.

The plan, which Republicans plan to introduce as soon as April, will include an expansion of health-savings accounts and allow consumers to purchase insurance across state lines. It will include changes to health-care liability rules, she said.

Culled in part from previous legislation Republicans have offered, the plan may preserve the health-care exchanges, though ease federal requirements on insurance plans that she said have turned them into a "one-size-fits-all" approach.

"All of this is about providing an individual with more affordable choices within the marketplace to be able to make the best decisions," McMorris Rodgers said.

The concern about a president "unilaterally deciding what the law is going to be, when he's going to delay it" adds to Republicans' apprehension about moving immigration and other major bills to the floor, she said.

Immigration plan

Immigration, for one, "needs to be done at the right time, and so whether or not we can get to where we need to be this year is still to be determined," she said.

Republicans have rejected acting on a Senate-passed bill and rolled out a plan of principles on immigration at a party retreat earlier this year.

The plan, which includes increased border security, doesn't have enough votes among Republicans alone to pass it, she said. Any immigration measure in the House would need Democratic votes to advance, she said.

House leaders are also looking at the 2014 election picture in the Senate, where Democrats are defending 21 seats to the Republicans' 15. Several analysts, including Nate Silver of FiveThirtyEight.com, have said Republicans are favored even if narrowly to win control of the Senate in November.

"That's all part of the consideration," she said.

Women voters

Control of the Senate will hinge in part on being able to close a gap in support among women voters in states like North Carolina and Louisiana, where female Democratic incumbents are defending their seats in states that Republican Mitt Romney carried in the 2012 presidential election.

Obama beat Romney by 11 percentage points among women voting in 2012, according to exit polling.

McMorris Rodgers, whose leadership position puts her in charge of messaging, said Republicans will need to take lessons from the 2012 election in which party candidates weren't trusted and didn't connect well enough with women voters.

Republicans in 2012 suffered from "how we have allowed ourselves to be branded and defined by our opponents," she said, pointing to Democratic accusations that Republicans were conducting a "war on women."

"It was very detrimental and very costly" when candidates such as former Republican Representative Todd Akin of Missouri said "legitimate rape" victims rarely get pregnant, she said. "It fed that narrative and it was very damaging."

McMorris Rodgers has led recruiting of women Republican candidates and said her goal is to eventually double the number of women in the House.

Republicans have held training sessions for male candidates who may run against women challengers. When speaking to women voters, policy counts and "tone matters for the Republicans," she said.

With assistance from Nicholas Johnston and Alex Wayne in Washington.

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