Today voters in Florida, Illinois, Missouri, North Carolina and Ohio head to the polls in what could be decisive contests in both the Democrat and Republican races for the presidency.

On the Republican side, the winner-take-all primaries in Florida and Ohio are seen as pivotal, and could give Donald Trump an opportunity to cement an overwhelming delegate lead.

Currently, Trump holds a commanding 18 point lead in the RealClearPolitics polling average over home state Senator Marco Rubio.

Rubio’s planted his flag in Florida as a last stand for his campaign, after a dismal primary showing where he won only three contests — Minnesota, Puerto Rico and Washington, D.C.

Despite support from the entire GOP establishment — and the rest of the field who scheme to give one candidate a chance to defeat Trump — Rubio has failed to make the case to the voters who sent him to the Senate that they should promote him to the role of Commander-in-Chief.

The GOP establishment and Rubio Super PACs flooded the airwaves with over $10 million in negative attack ads that have yet to make a dent in Donald Trump’s lead in the polls.

99 delegates are at stake in the Florida Primary and heading into the day, Trump appears to hold a significant lead that will be difficult for other candidates to overcome.

The establishment’s scheme to stop Trump is running more efficiently in Ohio.

The last round of public polls give Governor John Kasich a four point lead over Trump in the race to secure Ohio’s 66 delegates.

But while most of the attention today is focused on Florida and Ohio, the delegate-rich states of Illinois, Missouri and North Carolina also hold primaries that could be just as decisive as the “Big Two.”

Illinois and Missouri will award their 69 and 52 delegates, respectively, on a winner-take-all basis by congressional district.

Trump currently leads all public polling in both states, so a strong win in both today could make up for a loss in Ohio.

On the other hand, Ted Cruz is polling a strong second and has committed hundreds of thousands of dollars to new TV ads in Illinois and Missouri. Upset wins in these states would narrow Trump’s delegate margin, setting the Republican Party on a path to a contested convention.

North Carolina will award their 72 delegates on a proportional basis, depending on each candidate’s percentage of the vote.

Trump heads into that primary holding a double-digit lead in the RealClearPolitics polling average.

For the Democrats, Hillary Clinton looks to be cruising in Florida. Clinton holds a 29 point lead over Bernie Sanders in the RealClearPolitics poll.

And while the polls had her leading by over 20 points in Michigan, where she actually ended up losing, Sanders has barely contested the state, making it look as if Hillary will sweep most of the delegates.

The key contests for the Democrats will be held in Illinois and Ohio.

Sanders, coming off his upset win in Michigan, looks to see if he can continue to parlay his opposition to trade deals for wins in two more Midwestern industrial states.

Polling momentum is on Sanders’ side in Ohio, where just ten days ago Hillary held a 20 point lead that has since narrowed to single digits.

In Illinois, the two most recent polls show a split decision. Clinton leads by three in the Public Policy Polling survey and Sanders tops Clinton by two in the CBS/YouGov poll.

All of the polling talk will come to an end tonight when the polls in North Carolina close and results begin to pour in across the country.

By the end of the night, will both parties have a clear picture as to who their nominees will be — or will we, the voters, produce another split decision that extends this unpredictable primary process?