(CNN) The special election race in Ohio's 12th Congressional District between Republican Troy Balderson and Democrat Danny O'Connor appears to be going right down to the wire.

A Monmouth University poll released Wednesday shows Balderson receiving 44% support and O'Connor pulling 43% with 11% of respondents saying they are undecided. That's a shift from a little over a month ago, when Monmouth found Balderson leading O'Connor by 10 points.

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Tuesday's election in central Ohio is the final test for the parties to gauge where they are in advance of the November midterm elections.

The poll comes just days before President Donald Trump heads to central Ohio on Saturday to stump for Balderson. The trip appears to be an attempt to fire up the Republican base, but Democrats close to O'Connor's campaign hope it will also spur Democratic excitement and turn off Republicans wary of Trump. The President's approval in the district stands at 46% with 49% saying they disapprove of his job performance.

Independent voters look to be boosting O'Connor's prospects, backing the Democrat over Balderson by a 48% to 32% margin -- with 17% undecided. That's a swing from the 33% to 30% split in favor of Balderson in June, when 33% were undecided.

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