Additionally, Wisconsin is the site of one of the nation's most hotly contested U.S. Senate races. While a new poll has Democratic Rep. Tammy Baldwin with a small lead, a poll released a couple of weeks ago had Republican Tommy Thompson with an even smaller lead, meaning the race is essentially a dead heat. As mentioned earlier, control of the U.S. Senate is at stake in the outcome of this race -- which will most likely come down to a percentage point or two. The outcome will significantly impact the policies of our country for years to come.

On another note, Baldwin's win would make history. She would become the first openly gay person elected to the United States Senate.

Indiana

Though 2004 Democratic presidential nominee John Kerry lost the state of Indiana badly (pdf), President Obama managed to squeak out a win in 2008. The margin? Just 30,000 votes (pdf). The president seems unlikely to repeat this feat this election, with polls showing him trailing Mitt Romney by more than 10 points; however, Indiana could be the state that decides which party will control the United States Senate.

Democrats hold the slimmest possible Senate majority, and since many key votes, among them health care reform, have fallen largely along party lines, the entire legislative agenda for the next few years will be decided not just by the presidential election, but by which senators are elected or re-elected on Tuesday. This is why, despite the fact that Indiana Senate candidate Richard Mourdock may have cost Mitt Romney the presidential election with his controversial comments on rape (Romney had just endorsed and filmed an ad for Mourdock, which he declined to rescind), the national Republican Party has rallied to Mourdock's aid. New polls make it clear that this will be a close race, which means every vote will count.

Pennsylvania

Like each Democrat before him dating back to 1988, President Obama carried the state of Pennsylvania in the presidential election. The president won by about half a million votes in 2008 (pdf), which sounds like a lot until you consider that the population of Pennsylvania is nearly 13 million. (The president's Democratic predecessor, 2004 nominee Sen. John Kerry, only won the state by two percentage points (pdf).) A new poll indicates that this year's presidential election will be even closer than the last. Though he held a double-digit lead last month, the most recent polling data show Romney and President Obama virtually tied in the state. It's worth noting that up until Oct. 28, just over a week before Election Day, Pennsylvania voters were still being mailed fliers with the outdated voter-identification requirements listed.

With regard to the senate race: While polls have shown Democratic Sen. Bob Casey with a healthy lead over his Republican opponent, now that Romney appears to be gaining momentum in the state, conservatives have begun investing more heavily in the closing weeks of the campaign in an effort to unseat the Democratic incumbent, perhaps betting it will come down to the wire.

Keli Goff is The Root's political correspondent.

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