The Maryland primary results will determine which presidential contender gets the state's 37 delegates in the winner-take-all contest.
Two late polls show him leading by margins of 17 and 25 percentage points. In 2008, John McCain defeated Huckabee in Maryland by 55 to 29 percent -- not far from where the most recent polls put Romney and Santorum today -- and won all of its delegates because he carried every county and all eight congressional districts. Nate Silver of The New York Times believes that Romney is likely to win all but one or two of Maryland's districts on Tuesday.
Click here for a rundown on who's ahead in the race for the Republican presidential nomination.
Below, a live blog of the latest developments to unfold on primary day.