Nationally, Mitt Romney has regained some essential momentum among the most conservative Republicans and independents who had soured on him in late February, according to a new Washington Post-ABC News poll.

The former Massachusetts governor is now more competitive with Rick Santorum for his party’s staunchly conservative base, just as the GOP nominating contest rolls into Illinois on Tuesday. Romney still scores fewer strong backers, but the new numbers provide an opportunity for him to settle stubborn issues again reflected in last week’s Alabama and Mississippi primaries.

In the two southern primaries last Tuesday, Romney lost “very conservative” voters by large margins to both Santorum and former House speaker Newt Gingrich, according to exit polls.

Now, 64 percent of the most conservative Republicans and independents express favorable views of Romney, up from a low of 43 percent three weeks ago. The number rating him unfavorably is well off its peak. At 70 percent positive, and 14 percent negative — 11 percentage points fewer than Romney — Santorum still has the edge here, particularly when it comes to intensity, but it’s narrower than it was three weeks ago.

Both Romney and Santorum outpace Gingrich by a wide margin: for the first time in polls this cycle, the number of very conservative Republicans and independents expressing favorable views of the former speaker has dipped below the 50-percent mark (49 percent). Just two weeks ago, Gingrich was at 67 percent in the group.

For much of the campaign, Gingrich has faced sliding numbers among the general public, and he’s showing new weakness in the GOP itself. Half of all Republicans have unfavorable impressions of him, the percentage doubling in the past three months.

Among Republican men, Gingrich draws about evenly (48 percent have favorable views; 47 percent negative ones); GOP women tilt negative (37 to 53 percent).

By contrast, Santorum is making progress among Republican women. Fully 66 percent of GOP women now express favorable views of the former Pennsylvania senator, a high mark for him in polls since the start of voting in January. Only 18 percent say they have unfavorable views. GOP women also tend to have positive impressions of Romney, but less so (59 percent favorable; 32 percent unfavorable).

None of these three Republican contenders is above water on basic popularity among all women nationally, or among men.

The poll was conducted March 14 to 18, among a random national sample of 1,004 adults. Results from the full poll have a margin of sampling error of plus or minus 3.5 percentage points.

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