Wondering what to look for as the presidential results start to roll in tonight? We've made it easy: Below, check out CBSNews.com's guide to when the polls close in key states and what the results will tell you about how the election seems to be breaking.

In states where the race is not close, CBS News and other media outlets will be able to call the state at poll closing based on exit polls. In tighter states - and most, if not all, of the battlegrounds will fall into this category - there won't be a call at the close. But CBS News will be able to talk about the exit polls and potentially discuss which candidate appears to have an advantage; we will also be able to break down the returns that have come in and what they tell us.

CBS News will be on air with coverage starting at 3 p.m. Alaska Standard Time, and KTVA.com will provide continuous coverage throughout the day and into night.

3:00 p.m. AKST

Polls close in six states - but Virginia is the one to watch.

Virginia

13 electoral votes

2008: Obama won by 6.3 percent

2004: Bush won 8.2 percent

Thanks to a population boom in Democratic-leaning Northern Virginia and an influx of minority voters, President Obama turned the Old Dominion State blue four years ago for the first time since 1964. Polls show the state to be exceedingly tight this time around. Mitt Romney, who enters Election Day with a narrower path to the 270 votes necessary for victory, will see that potential path shrink even further if he falls short here.

3:30 p.m. AKST

Polls close in three states - including two battlegrounds, Ohio and North Carolina.

Ohio

18 electoral votes

2008: Obama won by 4.6 percent

2004: Bush won by 2.1 percent

The Buckeye State has been the biggest battleground of the 2012 campaign. Both candidates have made more campaign stops here than anywhere else, and with good reason: It is the lynchpin of Mr. Obama's attempt to build a firewall in the Midwest to ensure victory in case he falls short elsewhere. If Mr. Obama wins here and in Wisconsin to the north - as well as Pennsylvania and the other states he is expected to win - he'll be just a few votes short of 270 with plenty of battlegrounds outstanding.

North Carolina

15 electoral votes

2008: Obama won by 0.3 percent

2004: Bush won by 2.9 percent

A must win for Romney, if only because it is the one battleground state where he held a clear lead entering Election Day. If Romney loses here, he's almost certain to have a very bad night. Though the Obama campaign has insisted it has not given up on North Carolina, where young and minority voters drove the president to a surprise victory four years ago, Mr. Obama's decision not to campaign here since the Democratic National Convention in Charlotte in early September tells a different story.