Millions of dollars have been spent, thousands of ads have been aired and the Florida Senate race ... remains in a flat tie.

A Quinnipiac University poll released Wednesday finds 49 percent of likely Florida voters back Democratic incumbent Bill Nelson and 49 percent support his Republican opponent, Gov. Rick Scott.

“The Florida Senate race, one of the most important this election year, is a dead heat,” said Peter A. Brown, assistant director of the Quinnipiac University Poll.

It's the first independent poll to come out since the explosive gubernatorial primary last week where Tallahassee Mayor Andrew Gillum scored a massive upset and won the Democratic nomination. He'll face Republican Congressman Ron DeSantis in the Nov. 6 election in a matchup of fierce partisans at the top of the ballot that could reshape the contours of a Senate contest that was expected to play more toward the political center.

A Quinnpiac poll released Tuesday showed the race between Gillum and DeSantis a virtual tie as well.

On the heels of both Quinnipiac surveys, University of Virginia political scientist Larry Sabato declared Florida "the purplish ground zero in the 2018 midterms."

Florida is one 10 states expected to determine who controls the Senate next year. Republicans hold 51 of the chamber's 100 seats.

Wednesday's poll finds Scott leading among white voters (55 percent-44 percent), Hispanics (59-39 percent), and Republicans (92-7 percent), while Nelson is winning among black voters (90-5 percent), Independents (56-43 percent), and Democrats (89-8 percent).

“The campaign is a prototype of our nation's political environment," Quinnipiac's Brown said. "The key in close elections like this one often lies with independent voters. So far, Sen. Nelson has the edge with this swing group."

The poll is relatively good news for Nelson who has been heavily outspent by Scott, a dogged campaigner whose approval ratings as governor have been on the rise. Nelson released his first television ad last week, four months after Scott began airing his.

By 49 percent to 43 percent, Florida voters approve of the job Nelson is doing as a senator while voters approve of the job Scott is doing as governor 51 percent to 46 percent, the poll found.

The poll included responses from 785 Florida likely voters and was conducted from Aug. 30 through Sept. 3. It has a margin of error of plus or minus 4.3 percentage points.

While many political pundits have said this year's midterms will likely be a referendum on President Donald Trump, nearly half of those polled in Florida – 46 percent – said he's not an important factor in their choice for Senate. Of those who think he is, 26 percent said they see their vote as a chance to support the president while 25 percent said they view the election as a chance to oppose him.

The poll also found that nine of 10 Florida voters have made up their mind on the Senate race, meaning mobilizing supportive voters to turn out will be crucial to victory. To that end, Vice President Mike Pence will be joining Scott Thursday at campaign events in Orlando and The Villages.

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