(CN) - Democrat Conor Lamb has taken the lead over Republican Rick Saccone in Pennsylvania’s closely watched special election in the state's 18th Congressional District, according to the a new Monmouth University Poll.
A day before voters in the district head to the polls, Lamb holds a 6-point advantage, leading Saccone 51 percent to 45 percent.
One percent of voters polled support a third-party candidate, while 3 percent remain undecided.
The polls depends on a model that anticipates a surge in Democrats at the polls. Another model, based on turnout in past midterm cycles, still has Lamb ahead, but by a far slimmer 2 percent.
The election will fill the vacancy created by the departure of incumbent Republican Tim Murphy. Murphy announced his resignation in October 2017, following reports that he encouraged a woman with whom he had an extramarital affair to have an abortion.
President Donald Trump won Pennsylvania's 18th Congressional District by close to 20 points in 2016, but Republicans have been bracing for a Democratic upset for several weeks as polls by Monmouth University and other organizations have shown the race teetering back and forth, with Lamb and Saccone alternately shown to have a small lead.
A survey conducted by Monmouth last month found the Republican state lawmaker leading by a small margin.
“This district has voted overwhelmingly Republican in recent elections, but a large number of these voters have blue-collar Democratic roots. Lamb seems to have connected with them,” said Patrick Murray, director of the Monmouth University Polling Institute.
“When added to a potential Democratic surge that has been building for weeks, Lamb appears to
have picked off enough Republican-leaning voters to take a lead going into this contest’s final weekend.
It would mark an extraordinary swing from Trump’s nearly 20 point victory here in 2016 if he could hold
on to win,” Murray said.
Republicans have dumped millions of dollars into the race to keep it in GOP hands and fend off an embarrassing loss, and President Trump himself visited the district over the weekend to throw his support behind Saccone.
Groups supporting GOP candidates have spent more than $10 million on the race, according to published reports.
Meanwhile, former Vice President Joe Biden and U.S. Rep. Joe Kennedy III, D-Mass., have both made appearances in support of Lamb.
The latest Monmouth University poll was conducted from March 8 to 11 and surveyed 372 likely voters in the district. The survey has a margin of error of 5.1 percentage points.
But it likely does not portend the future of the district.
Whoever emerges victorious in the special will likely have to fight hard to keep his seat in the regularly scheduled November 2018 election.
That's because the Pennsylvania Supreme Court struck down the state’s current congressional map as too gerrymandered in favor of the Republican party, and last month imposed new district lines that are friendlier to Democrats.
The new map splits most of the current 18th Congressional District between the new heavily Republican 14th District and a more competitive 17th Congressional District.
If Saccone wins on Tuesday, he has said that he would seek re-election in the 14th Congressional District, but if Lamb wins, he is expected to go run in the 17th Congressional District taking on incumbent Republican Rep. Keith Rothfus.
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