The Ohio Senate race is a dead heat, with Democrat Sherrod Brown at 47% and Republican Jon Husted at 44% in a new Suffolk University/USA TODAY Ohio Network poll released Tuesday.

The 3-point gap is within the poll’s 4.4-point margin of error, making the race a statistical tie. An earlier Marist poll had shown Brown leading 51% to 43%.

The contest is among the most closely watched Senate races of the midterms, with control of the chamber potentially at stake. Both parties have poured resources into the state, blanketing airwaves with advertising.

Pollsters cautioned that the electorate remains volatile, with a significant share of voters still undecided six weeks before polling day. The final stretch is expected to see intense campaigning from both camps. Brown, a longtime incumbent known for his populist economic message, is seeking to hold a seat Democrats cannot afford to lose. Husted, the state’s lieutenant governor, has the backing of the national GOP, which sees Ohio as a prime pickup opportunity in its bid to expand the Senate majority.