After $4 billion spent by campaigns and outside groups on the midterms, voters are finally heading to the polls.

Everyone knows that it will be a bad night for Democrats. Republicans will pick up more seats than they had. The biggest question of the night: will Republicans win at least six seats to regain control of the Senate?

Even if the GOP wins back control, it’s not clear if it will be a wave election or if Republicans will squeak by with just enough seats.

Keep an eye on the Senate races in New Hampshire, North Carolina and Virginia. Those results will come in first on Tuesday — all three states will be difficult for Republicans to flip. But if any of these states go Republican, look for that as a sign that it is going to be a very good night for the GOP.

Here is The Daily Caller’s cheat sheet to the most interesting Senate races to watch on Tuesday as the results start coming in.

Kentucky Senate

Why It Is Interesting: Nobody stands to benefit more on Tuesday than Kentucky Sen. Mitch McConnell. If he beats Democratic opponent Alison Lundergan Grimes and Republicans net at least six Democratic seats, McConnell becomes Senate majority leader.

Polling: The RealClearPolitics polling average shows McConnell leading Grimes 48.3 percent to 41.8 percent. (RELATED: Alison Lundergan Grimes Again Dodges Whether She Voted For Obama)

Highlights: Grimes repeatedly refused to admit whether she voted for President Barack Obama; McConnell ran an ad shedding light on Grimes’ family’s “Hugh Jass” burger restaurant; Grimes released ads showing her shooting guns. (RELATED: Alison Lundergan Grimes Is Shooting Guns Again)

Colorado Senate

Why It Is Interesting: If Republican Rep. Cory Gardner defeats incumbent Democratic Sen. Mark Udall, that means the “War on Women” argument against the GOP isn’t working. Udall has devoted much of his campaign trying to appeal to women by attacking Gardner on abortion, though polling suggests the one-issue strategy has not worked.

Polling: The RealClearPolitics polling average shows Gardner leading Udall 46.4 to 42.6 percent.

Highlights: Udall featured a little girl in an abortion ad; Deadspin badly fumbled the piece on Gardner, falsely accusing him of lying about playing football.



Kansas Senate

Why It Is Interesting: Independent candidate Greg Orman could complicate the GOP’s hopes to win back control of the Senate if he defeats incumbent Republican Sen. Pat Roberts. The Democratic candidate in the race dropped out.

Polling: The RealClearPolitics polling average shows Orman leading Roberts 42.5 percent to 41.8 percent.

Highlights: Pat Roberts barely survived the GOP primary challenge from conservative Milton Wolf, who is also a distant cousin of President Barack Obama; Roberts came under fire for listing his Virginia home as his principal residence; Greg Orman refuses to say which party he would caucus with if elected.

New Hampshire Senate

Why It Is Interesting: Could former Massachusetts Sen. Scott Brown become New Hampshire’s next senator? Polls show a close race with incumbent Democratic Sen. Jeanne Shaheen.

Polling: The RealClearPolitics polling average shows Shaheen leading Brown 48.4 percent to 45.9 percent.

Highlights: Debate gotcha question for Scott Brown backfires on journalist; With chicken mascot, Republicans make Shaheen’s lack of town halls an issue; Scott Brown runs immigration ads. (RELATED: Scott Brown Hits Shaheen On Immigration In New Ad)

Iowa Senate

Why It Is Interesting: Republican Joni Ernst is poised to become the first woman elected to represent Iowa in Congress, with polls showing her leading Democrat Bruce Braley heading into election day.

Polling: The RealClearPolitics polling average shows Ernst leading Braley 46.9 to 45.1 percent. The trusted Des Moines Register poll, released over the weekend, shows Ernst up by 7 points.

Highlights: Ernst got famous in her primary by saying “castrating hogs” is good preparation for Washington D.C.; Braley committed one of the most memorable gaffes of the cycle by talking condescendingly about Iowa farmers during a fundraiser.

Georgia Senate

Why It Is Interesting: If neither Republican David Perdue or Michelle Nunn win more than 50 percent of the vote on Tuesday, a run-off will be held in January. Under that scenario, the race could potentially decide which party wins control of the U.S. Senate.

Polling: The RealClearPolitics polling average shows Perdue leading Nunn 46.5 percent to 44.7 percent.

Highlights: Nunn’s entire campaign plan leaked; Democrats relying on black pastors and racial fear to motivate African-American vote; Perdue signs a voter’s insulin pump. (RELATED: Democrats Relying On Black Pastors — And Racial Fear — In Georgia Senate Race)

Louisiana Senate

Why It Is Interesting: In the state’s unusual jungle primary, if no candidate in the race wins more than 50 percent, a run-off will be held in December with the top-two finishers.

Polling: The RealClearPolitics polling average shows incumbent Democratic Sen. Mary Landrieu with 39.6 percent, Republican Bill Cassidy with 34.1 percent and Republican Rob Maness with 10.4 percent. In a hypothetical run-off match up between Landrieu and Cassidy in December, the polling shows Cassidy leading Landrieu 48 to 43.4 percent.

Highlights: Landrieu helps LSU fans do a keg stand; Landrieu: Obama and I aren’t popular in the South because of racism and sexism; Senate candidate recalls being in Pentagon on 9/11. (LANDRIEU: Obama And I Aren’t Popular In The South Because It’s Racist And Sexist)

Arkansas Senate

Why It Is Interesting: Polls indicate that Arkansas Republican Rep. Tom Cotton, a Harvard law grad and veteran of the wars in Iraq and Afghanistan, will defeat incumbent Democratic Sen. Mark Pryor.

Polling: The RealClearPolitics polling average shows Cotton leading Pryor 48.3 percent to 41.2 percent.

Highlights: Pryor attacks Cotton over Ebola, then awkwardly struggles to assess Obama’s performance. (RELATED: Mark Pryor Botches A Reporter’s Simple Question)

North Carolina Senate

Why It Is Interesting: Despite being labeled one of the most vulnerable incumbent Democratic senators, Sen. Kay Hagan is fending off Republican Thom Tillis in a state that voted for Mitt Romney over President Barack Obama in 2012.

Polling: The RealClearPolitics polling average shows Hagan ahead 45 percent to Tillis’ 43.4 percent.

Highlights: Pro-Hagan fliers use a lynching image, warning of ‘Obama’s Impeachment’ if Democrat loses; Libertarian senate candidate in North Carolina could be a spoiler; ‘Uncle’ Thom Tillis blasted at Hagan rally.

Alaska Senate

Why It Is Interesting: With millions pouring in from outside groups, Republican Dan Sullivan has a small lead over incumbent Democratic Sen. Mark Begich.

Polling: The RealClearPolitics polling average shows Sullivan leading Begich 46.2 percent to Begich’s 43.6 percent.

Highlights: Begich is under fire for a“Willie Horton-styled” ad against Sullivan; Begich admits to voting for Obama but calls him “not relevant”; The father of a soldier killed in Iraq makes a moving ad for an Alaska Senate candidate.

Virginia Senate

Why It Is Interesting: All polls have showed incumbent Democratic Sen. Mark Warner leading former RNC chairman Ed Gillespie. But recent polls reflect that Gillespie is down by just single digits. In fact, one released over the weekend said he was down just four. If Gillespie somehow pulls off a victory, it would easily be the Senate upset of the night. Still, some Republicans privately speculate that Gillespie is running this year to get his name out for a future gubernatorial fun.

Polling: The RealClearPolitics polling average shows Warner leading Gillespie 48.5 percent to 38.8 percent.

Highlights: Gillespie runs ad accusing Warner of not only voting with President Obama 97 percent of the time, but of playing “politics with a lifetime appointment to the federal bench”; Warner attacked Gillespie for running a lobbying firm that represented Enron; Warner criticized by Gillespie for taxpayer-funded private plane usage; Gillespie works to win over skeptical conservative base.

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