This analysis was written by CBSNews.com senior political editor Vaughn Ververs.
Nearly two years after the 2008 campaign officially began, Election Day is finally here. The path from there (when John Edwards announced his candidacy in December of 2006) to here has been unpredictable at times and unprecedented in so many ways.
No matter what happens, history will be made when the voters have had their say and elect either the first black president or the first woman vice president.
Barring a repeat of 2000, the campaign will come to an end at some point late tonight or perhaps in the wee hours of Wednesday morning. The most expensive election in U.S. history will be in the books and all the thousands of TV ads as well as all those national and state polls will be rendered meaningless.
There's not much left to be said as voters head out to vote in what both sides are predicting to be record numbers. But, plenty of questions remain to be answered as the results come in. Here are 10 questions for Election Day:
1. What Should You Watch For Today? With turnout projections extremely high, long lines and reports of problems at the polls throughout the day will be worth keeping an eye on. Weather forecasts for much of the nation show few potential trouble spots but rain could be an issue stretching from southeast Pennsylvania to parts of Virginia and North Carolina - all battleground states.
It's not at all unlikely that long lines, particularly in urban areas, will result in some states or cities extending voting hours, which could delay results in key places. Also, large numbers of voters means more to count for overworked election officials, which could mean the results coming in slower than normal.
Exit poll or purported exit poll information could spread anywhere on the Internet but be wary of anything you see. Quarantine procedures virtually guarantee that real data does not get out until much later in the day and, even then, anything you see could easily be early and incomplete. Beware.
Jeff Greenfield has a more complete breakdown of what to keep an eye on once the polls have closed, but right off the bat, before 8:00pm Eastern, the big four targets are Virginia, Indiana, North Carolina and Ohio. All are states carried by Republicans in at least the last two presidential elections and are crucial to John McCain's hopes. If he's doing well in those four states, it could be a long night.
2. Can Obama Win A Mandate? Democrats haven't won big mandates in presidential elections in recent history (and even Republicans have to go back a way to find their last big victory). However, Democrats' hopes have been raised by the polls leading up to the election that this could be a defining year, both nationally and in the Electoral College.
So, what would a mandate look like? Compared to the last four elections, it wouldn't take much to win a big one. Bill Clinton won a whopping 370 Electoral Votes in 1992 but only managed a popular vote plurality of 43 percent, thanks to Ross Perot's nearly 19 percent grab in that election as a third-party candidate. Clinton bettered his haul in 1996, winning 379 Electoral Votes, but still fell just short of a majority in the popular vote. Nobody needs to be reminded about the narrow split decision in 2000 and in 2004, George W. Bush just barely managed a majority in both.
A convincing popular vote victory appears within reach for Obama. With big turnout by black and young voters, Obama could run up his vote in states he's unlikely to win - like Mississippi, Alabama and Arkansas - and in states he should win easily, like California and New York. A big Electoral College win is a bit trickier but not out of the question. Should states like Ohio, Pennsylvania and Florida all tilt Democratic this year, it probably means he's also winning Virginia and Colorado - perhaps even North Carolina and Indiana.
Fifty-three percent or higher in the popular vote combined with 338 or more Electoral Votes wouldn't be a 49-state, 59 percent Reagan sweep, but a mandate nonetheless.
3. Can McCain Pull Off A Shocker? Don't think this isn't a real possibility. The odds are long, no doubt about it, but it's not out of the question. So much has been made about this campaign taking place on largely Republican territory that it's often forgotten that it is just that - Republican territory.
George Bush didn't win two presidential elections by pure luck - he did it with very reliable get-out-the vote machines in many of these same states. For all the hype and attention given to Obama's organization, Republicans have flown under the radar screen. But senior party officials say they are revving it up to the hilt and remain confident that there is at least a path to 270. If McCain can take places like Ohio and Virginia, that probably means teetering states like Indiana and Missouri can be held as well.
While Obama has made real inroads in the west, Pennsylvania could be this year's Ohio or Florida from past elections. It's an inside straight to be sure, but the cards left in the deck give them a shot.
4. What Does Massive Turnout Mean? Both sides in this election (and isn't it telling that third party candidates have all but disappeared on all levels this year?) are predicting record turnout - at least in terms of raw numbers, if not percentage. There could be as many as 130 million Americans casting votes.
Conventional wisdom holds that increased turnout will benefit Obama in a big way. That might well be true. But even if larger numbers of black and young voters turn out to vote, their totals as a percentage won't have the same impact if Republicans increase their share of the pie as well. Keep this in mind when you begin to hear about large turnout tomorrow: In 2004, Democrats not only far exceeded their turnout in Ohio, John Kerry received more votes than any other presidential candidate of his party, ever. But he lost, because Republicans did the same. Huge turnout could be a wash but probably benefits Obama, at least in the popular vote.
5. Can New Hampshire Happen Again? Remember the New Hampshire primary? Most polls had Obama cruising to a big win, some by as many as ten points. It was supposed to be the finishing blow to Hillary Clinton, who was staggering after a third-place finish in Iowa. But Clinton came back to win and take Obama all the way to the very end of the primary season.
Another bothersome signal for Obama is that he sometimes over-performed in exit polling during the primary season, getting much less of the actual vote than projected. There's no way to tell whether many of these polls heading into the election are right or wrong until after the votes come in, but keep an eye out in those states where Obama remains in the lead, yet under 50 percent. If his support is being exaggerated, those are the first places you'll see it.
6. What Will The Palin Effect Be? There is absolutely no doubt about it - love her or hate her, Sarah Palin has been the most interesting part of the last two months of the campaign. Since bursting onto the scene, the Alaska Governor has become arguably the most divisive figure in American politics today.
In the eyes of many analysts - and not a small number of Republicans - the choice of Palin has been a huge drag on the ticket. That view is backed up by a lot of polling data which shows that she has turned many moderate and independent voters away from McCain. But what none of that measures is the excitement she has generated among an evangelical base which was cool, at best, to McCain's candidacy. These are the people whose organizational networks have powered the Republican Party for more than two decades.
If you're inclined to write off Palin as a disaster of a pick, remember this: Before McCain had clinched the nomination, influential evangelical leader James Dobson proclaimed that he would never support him. After his pick of Palin, he enthusiastically came on board. For every potential vote in the middle McCain may have lost, he could gain one-and-a-half from reliable conservatives who may have stayed home otherwise.
7. Did "Joe The Plumber" Help? When "Joe The Plumber" stumbled upon Barack Obama canvassing in his Toledo, Ohio neighborhood, he inadvertently gave voice to a McCain economic message that had been a bumbling one at best. After initially calling the economy fundamentally strong, then "suspending" his campaign to work on the Wall Street bailout, McCain was lost on the most important issue for voters.
Enter "Joe The Plumber," whose short exchange with Obama got the anti-tax juices running among Republicans. His name has become a campaign staple and served to revive the image of the Democratic Party as tax-and-spend. Polls still show that voters are just as likely to believe McCain would raise taxes as they do Obama but at least it's given McCain a stable message. It could help, especially in places like Ohio and western Pennsylvania. If McCain wins, "Joe The Plumber" will have a special place in campaign history.
8. Did Clinton Voters Come Home? It's been the biggest concern for Democrats since the primary season ended - will Hillary Clinton's supporters come home? Polls have indicated that, in large part, they have. And Clinton, along with her husband, have coalesced around Obama in the closing weeks of the campaign.
But there remains a question mark about whether her supporters, especially the so-called "PUMAS," (Party Unity My A$%), will stay home - or even vote for McCain. In most instances it won't matter as many of them live in reliably blue states. But in those places where Clinton thrashed Obama in the primary campaign - particularly Ohio and Pennsylvania, those blue-collar men and women who supported Clinton could be a real benefit for the GOP if they move to McCain.
9. How Big Was The Bush Drag? In many respects, it's almost a miracle that McCain enters Election Day with any chance at all. The latest CBS News poll tells the tale - President Bush has reached the lowest approval rating for any president in recorded history. Just 20 percent of voters approve of the job he is doing.
That's the kind of head-wind Republicans are running against. From top to bottom, the GOP brand has been tarnished. The war in Iraq, a floundering economy and governmental mismanagement at all levels have produced a frustrated electorate hungry for a message of change. It hasn't been all Bush's fault, but he certainly gets the blame and has become the kind of drag on the ticket that could pull down a whole lot of candidates.
10. Can Democrats Hit 60 In The Senate? It's not going to be easy, but Democrats are within striking distance of winning a filibuster-proof majority in the U.S. Senate. With a larger majority in the House all but certain, the party could rule nearly unimpeded if that were to happen.
Democrats are almost certain to pick up Republican-held Senate seats in Colorado, New Mexico, Virginia and probably Alaska. They are favored in another three at this point - North Carolina, Oregon and New Hampshire. And Republicans are holding their breath in the Mississippi special election (where no party ID is on the ballot), Minnesota, Kentucky and Georgia (where there could be a runoff if no candidate gets over 50 percent of the vote in a three-way race).
Should a real wave sweep over the country today, it's not at all improbable to think that Democrats would pick up the nine seats they need to have that daunting majority. Then they'll have to deal with Joe Lieberman, the Democrat-turned-Independent who now caucuses with his old party but has endorsed John McCain enthusiastically. It's a reminder that politics doesn't ever stop, especially after a presidential election.
Happy Election Day, get out and vote.