Florida Gov. Rick Scott’s plans have been talked about for so long that it would have been shocking if he hadn’t announced his challenge to Democratic Sen. Bill Nelson on Monday. And now that the Republican governor is officially in, the Sunshine State is poised to host an expensive race with national implications.

Of course, Democrats are confident about Nelson’s re-election chances. But this will be a race unlike any other the senator has faced. Scott, who is personally wealthy, could not only invest tens of millions of dollars of his own money into the campaign, but also utilize national fundraising contacts as a former chairman of the Republican Governors Association.

Nelson had $8 million in his campaign account on Dec. 31 (first quarter Federal Election Commission reports are due April 15) and is used to outspending his opponents. He outspent GOP Rep. Connie Mack $17 million to $7.5 million in 2012 and GOP Rep. Katherine Harris $16 million to $9 million in 2006. That will not happen this year.

[Roll Call’s 2018 Election Guide]

Last week, the Democratic opposition research group American Bridge released a memo that downplayed Scott’s two statewide victories because they took place in favorable Republican years and he won narrowly.

But Nelson is part of a Democratic class that had the good fortune to run in 2006, a great year for the party, and in 2012, when President Barack Obama had his re-election machine running full throttle.

Nelson has also benefited from facing two weak opponents. Harris was infamously polarizing for her role as Florida secretary of state in the 2000 presidential election, and Mack never received the outside Republican support he was hoping for.

Of course, money isn’t the only important factor. Democrats look likely to benefit from a national electoral wave, which could make it difficult for Republicans to win in competitive states.

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But at a minimum, Democrats will need to spend time, money and energy re-electing Nelson in a race many race observers say will be decided by a couple of points in either direction. Those are resources that will be taken away from defending other vulnerable incumbents or expanding the playing field.

We’re changing our Inside Elections rating from Tilts Democratic to Toss-up.

Democrats probably have to re-elect Nelson to have a realistic chance at the Senate majority. Re-electing all of their own senators and taking over Arizona and Nevada is their most viable path. If Democrats end up losing Florida, then they’d have to compensate by winning a more Republican state such as Tennessee, Texas or Mississippi.