Which States Will Decide Which Party Controls The Senate? Election Day Will Be Particularly Heated In These States

The next four years will likely see a Democratic president, if polls are to believed. But what about the Senate during the next two? Which party controls it will matter in a myriad of ways, whether a majority-GOP Senate blocks potential Supreme Court nominees from Hillary Clinton or a Democratic Senate fights with the Republican House on issues like immigration reform and gun control. And unlike the race for president, there's plenty of uncertainty about the winning party. So which states will decide which party controls the Senate?

It's actually just a handful — really about five. But before the big reveal, here's where that number comes from. You start by looking at all the seats that are up for reelection. This year, the good news is with the Democrats. Most of the seats that are up for reelection are currently held by Republicans. Only 10 of the seats up for a vote belong to Democrats, whereas a whopping 24 Republicans are up for reelection. Then take a look at the polls to see how close they are.

Of all those races, according to a report from The Washington Post , only five are considered in play still. Because the races in Illinois and Wisconsin seem to safely be on their way to flipping blue, the Dems will need to win two or three of these five — two if Clinton is president and Tim Kaine can cast a tie-breaking vote on Senate matters, and three if Trump were to win. So pay special attention to these races as the results come in on election night.

1. Indiana

This state is the story of the retirees running again. The current GOP Senator came out of retirement to run in 2010, but is now re-retiring. That brings us to the Democrats' candidate, Evan Bayh, who had retired in 2011 but decided he would have another go at it this time around. He's polling just ahead of Republican Rep. Todd Young.

2. Nevada

This is the only seat that's currently held by a Democrat, Senate Minority Leader Harry Reid. With Reid retiring, the race is now between Democrat Catherine Cortez Masto and Republican Joe Heck. The race is currently too close to call, according to The Las Vegas Review-Journal.

3. New Hampshire

Here it's almost as though Trump is on the ticket for Senate, with Republican incumbent Kelly Ayotte coming under attack for her support of the GOP nominee, and then going down in the polls after finally distancing herself from him. That has all boosted Gov. Maggie Hassan's candidacy. She's now nearly neck-and-neck with Ayotte.

4. North Carolina

This state has an awfully close race, too. Two-term incumbent Republican Richard Burr is fighting to the finish line against Democratic challenger Deborah Ross. Trump and the Republican governor, Pat McCrory, who signed the anti-LGBT SB2, have been weighing him down, some insiders say. Despite all that, Burr currently has a slight lead.

5. Pennsylvania

Here, another GOP incumbent, Pat Toomey, is up against a Democratic woman, Katie McGinty. In the most expensive Senate race ever, McGinty has proved deft at accusing him of deflecting on the Trump question — Toomey still hasn't said who he'll vote for. The race is nearly a dead heat, despite Clinton polling ahead in the state.

So while you watch the results come in on election night, don't forget to keep your eye open for these Senate races. They will decide quite a lot.