In the 1st District, it is impossible to call the race between two Democrats vying for the nomination.
Wendy Rosen of Cockeysville, a businesswoman and advocate of the "Made in America" movement, led physician John LaFerla of Chestertown by 126 votes as of Wednesday, April 4, with all precincts reporting.
The district is currently represented in Congress by Rep. Andy Harris, R-Cockeysville. Harris faced no primary contest on Tuesday.
A third candidate in the race, small business owner Kimberly Letke of White Marsh, was well behind the top two with 13.9 percent of the vote, according to unofficial returns on the State Board of Elections website.
The race is too close to call because 1,196 absentee ballots cast in the contest have not yet been counted, and 387 absentee ballots mailed out to Democrats in the 1st District have yet to be returned, according to the Board of Elections website.
Absentee ballots received by April 13 will be counted, provided they were postmarked on or before Tuesday.
Rosen said she is confident she won, and she said she is already looking ahead to November.
"I believe that it's time for us to pull together and get this entire campaign together and move forward to beat Harris," Rosen said. "We need party reconciliation and a complete joint front together. If I had lost, I would do that for John."
But LaFerla said he is not conceding the election until all the absentees are counted.
"The reason I'm hopeful is if you look at the numbers that came in (Tuesday), the early vote showed me winning by a large margin," LaFerla said. "It's at least theoretically possible for me to have a definite win, and that's why I'm not conceding at this point."
LaFerla won 48.2 percent of ballots cast in early voting, building up a 10-point margin over Rosen heading into Tuesday. He said he hopes absentee ballots will break his way by the same margin, which Capital News Service calculates would reduce LaFerla's deficit to just four votes even if no more ballots are returned.
"We have to wait and see how they turn out," said LaFerla. He said he would want the ballots recounted "if the difference is three votes," for example, though he added, "but if the difference is (a substantial number), I wouldn't question that."
While LaFerla has the right to a recount, as would Rosen if the tally of absentee ballots were to put her in second place, Maryland has no provision for an automatic recount.
"The choice to do a recount would be that of the candidates," said Donna Duncan, elections management director at the State Board of Elections.
Rosen leads by half a percentage point, meaning if LaFerla were to request a recount, his campaign would have to pay for it, unless the new count gives him more votes overall than Rosen. The state will pay for a recount only if the difference between the two candidates is less than .1 percent of all votes cast.
Poll workers will begin counting absentee ballots Thursday.
Asked whether he would endorse Rosen if she is the nominee, LaFerla hesitated and said, "I expect I will, but I'm a little emotional right now. Let's just get this election done right now and go from there."
LaFerla earned late endorsements from moderate former Rep. Wayne Gilchrest, R-Kennedysville, and several abortion rights groups, including NARAL Pro-Choice Maryland and Planned Parenthood.
Meanwhile, Rosen had the backing of fellow Cockeysville resident Rep. C.A. Dutch Ruppersberger, the Democratic incumbent in the neighboring 2nd District, who was unopposed for re-nomination on Tuesday.
Rosen has raised $26,606 since she entered the race last November, and she loaned her campaign $75,000 late last month. LaFerla's campaign reported $70,695 raised over the full period, with no personal loans from the candidate.
The eventual Democratic nominee will face an "uphill battle" to unseat Harris, according to St. Mary's College professor Michael Cain.
"Clearly, the vote has been split, and that puts the Democratic Party in a much more difficult position," said Cain. "They have to bind up their party and get themselves behind one candidate."