Former Massachusetts Gov. Mitt Romney’s favorability ratings continue to be high among Republican voters. Republicans, by a margin of 61 to 18 percent, view him favorably; a new Washington Post-ABC News poll shows.

Romney's favorability ratings are the highest since March and his unfavorability ratings have declined from 29 percent in November.

Romney’s ratings are better than his nearest challengers. Former Sen. Rick Santorum comes closest, at 48 percent favorable and 18 percent unfavorable, while Rep. Ron Paul, R-Texas, comes in at 40 percent and  39 percent, respectively.

Among the general electorate, Romney is at 39 percent to 34, Paul 31 to 38, and Santorum 27 to 29, according to the poll.