WASHINGTON (AP) - Preliminary figures from an exit poll of Mississippi voters show the three leading Republican presidential contenders splitting the votes of the huge block of white born-again or evangelical Christians.

Rick Santorum has a slight edge among those voters in Alabama.

White born-again Christians accounted for 8 in 10 Alabamans on Tuesday, the most in any state polled this year. Such voters also comprised nearly 3 in 4 in Mississippi, a figure that is unsurpassed by any previous state to vote.

Santorum and Gingrich are running well among the strongest conservatives in both states. Romney is doing better with more moderate voters.

Romney has a small advantage with Alabama voters focused on the economy. In Mississippi such voters are split among the three rivals.