From now until Election Day, on November 6, we’ll be highlighting all the important midterm races in 2018. Today we will focus on 1 of the 9 “toss-up” Senate seats up for grabs which will determine the Senate’s balance of power next year. In Florida, the Senate race is shaping up to be a nail-biter. Longtime incumbent Democrat Bill Nelson is fielding a very tough challenge from Republican Rick Scott, the term-limited sitting Governor. Democrats genuinely need to hold this seat, and the race is already becoming very costly on both sides with spending on political ads skyrocketing around the state.

Scott had started the race 4 points down from Nelson, but the gap has narrowed to a dead heat, as Politico reports:

The nation’s most-expensive Senate race is a dead-even tie between Florida Sen. Bill Nelson and Gov. Rick Scott, according to a new Quinnipiac University poll.

The 49 – 49 percent race shows how Scott has narrowed a 4-point deficit since Quinnipiac last surveyed the race in February, but the results suggest that the three-term Democratic senator has so far weathered a storm of negative ads after Scott and Republican groups outspent Nelson and Democrats on TV ads by $30 million to $12 million as of mid-August.

Since Tuesday’s primary, however, Nelson’s camp has started to narrow the gap with Scott on TV. Democrats have recently placed about $55.4 million total on air in the biggest swing state, compared to $66.3 million from Republicans. TV ad spending is a must in a state as large and as competitive as Florida, which has 10 major media markets and can cost upward of $3 million weekly to advertise. So the cumulative $121 million in ad spending to date is set to grow significantly.

The tie race is no surprise in Florida, which has a history of razor-thin election margins. But what stands out in the poll is that 9 in 10 voters who have picked a candidate say they won’t change their mind by Election Day.

Peter A. Brown, assistant director of the Quinnipiac University Poll, said the electorate is polarized when it comes to party affiliation, gender and race and ethnicity.

The latest polling average from RealClearPolitics gives Scott a slight advantage:

Nelson is vulnerable, his approval ratings are less than 50 percent which is usually bad news for incumbents. That being said, he’s been a strong Florida politician, always riding a little more centrist than some of his Democratic colleagues which has continued to win him re-election since 2001. Being an incumbent for 17 years holds an out-of-the-gate advantage over many challengers, but with Scott being the sitting Governor, neither candidate is hurting for name recognition or fundraising profile.

Given the current environment, Nelson may still be slightly favored depending on whether a blue wave crashes in Florida. With a race this tight, and a highly competitive Governor’s race at the same time, voters in both parties will be motivated to come out for at least 2 statewide offices.

Florida will be one to watch on election night and even if Republicans lose the House, they could still end up picking up Senate seats like Nelson’s which might be the consolation prize.