Washington (CNN) -- The fate of endangered Democrats, vulnerable Republicans and control of the Senate will be decided in a matter of hours Tuesday as voters across the country head to the polls to chart the direction of the country for the next two years.
That is, of course, assuming control of the Senate does not hinge on razor-thin victories that trigger recounts and possibly runoff elections in two states.
Election Night will deliver clarity as well as confusion. There will, of course, be individual winners and losers, and the GOP is expected to easily hold, if not build upon, its majority in the House. But the great unknown is which party will control the Senate -- an important detail that will greatly influence President Barack Obama's final two years in office.
Republicans need a net gain of six seats to win control of the Senate and momentum seems to be in their direction.
With polls opening across the country, Election Day could also offer fresh evidence that the angry, anti-incumbent mood extends well beyond Washington, as the fate of several embattled governors will be decided on this night.
We may also witness the rebirth of a handful of political dynasties, as well as the crushing defeats of two high-profile, and much-hyped Democratic candidates: Texas gubernatorial candidate Wendy Davis and former American Idol star Clay Aiken, who is seeking a congressional seat in North Carolina.
And as the dust settles in the early morning hours of Wednesday, attention will turn to the next presidential and congressional elections that will occur just two years from now. That's assuming control of the Senate will not hinge on recounts and runoffs in Georgia and Louisiana.
To help guide you through the day and night, here are key moments to watch for to help make sense of an evening that can be equally overwhelming and exciting.
All Day: Controversy is the fuel that powers politics. It sparks discussions, excites activists, and forces change. Yet it has a dark underside on Election Day -- especially when there are charges of voter intimidation. In the past, supporters of both political parties have been accused of strong arm, nefarious tactics. Long lines, an insufficient number of ballots at polling locations and possible calls for judicial intervention to keep polls open could make for a messy, confusing and frustrating Election Day.
5 p.m. ET: We will start receiving results from the exit polls -- surveys that people take at designated polling locations after voting as well as phone surveys among millions of early voters. The preliminary data will likely provide a window into voters' thoughts about the most important problems facing the country, and what specifically they think about key issues such as the economy, health care, immigration and terrorism.
6 p.m. ET: Polls begin to close in Kentucky, which holds one of the most watched Senate races of this midterm election. Senate Republican Leader Mitch McConnell is locked in a competitive re-election battle with Secretary of State Alison Lundergan Grimes, a candidate Democrats hope can topple the minority leader.
7 p.m. ET: A dual focus on Kentucky and Georgia, which features the two best pick up opportunities for Senate Democrats. Winning one of these seats would take a little pressure off of Democrats who are playing defense for the remainder of the night. Knocking off McConnell would provide an added psychological boost for Democrats, but public polling shows that he has a single digit lead at this point in the race.
In Georgia, there are two Democrats hoping to build upon their families' political legacies. Michelle Nunn, daughter of former Sen. Sam Nunn, is running for the Senate seat vacated by GOP Sen. Saxby Chambliss. Jason Carter, grandson of former President Jimmy Carter, is seeking the governor's office -- the launching pad for his grandfather's successful presidential bid. But both contests are so close there is a belief that each race could go to a runoff if the candidates fail to receive more than 50% of the vote. If this happens, Carter would face off again against Gov. Nathan Deal on Dec. 2. Nunn and her Republican opponent David Perdue would face the voters again on January 6.
7:30 p.m. ET: Republicans have their first real, solid opportunity to win a Democratic seat in the open race to succeed Sen. Jay Rockefeller. Republican Rep. Shelley Moore Capito and Democratic Secretary of State Natalie Tennant are the respective nominees for their political parties. North Carolina will be closely watched as Sen. Kay Hagan, a Democrat, is trying to hold off an attempt by House Speaker Thom Tillis to send her home after one term. A victory by Republicans in North Carolina would be one of many critical building blocks the GOP is looking for to take back the Senate majority.
As a pop culture side note, Aiken will learn if his American Idol stardom can transform into a congressional victory. Spoiler alert: it's unlikely.
8 p.m. ET -- 9 p.m. ET: Polls across the country are closing in this hour, and in terms of the Senate majority the focus broadens to New Hampshire and Arkansas. In the Granite State, polls close at 8 p.m. ET and Democratic Sen. Jeanne Shaheen is facing former Massachusetts GOP Sen. Scott Brown in what has turned into an ugly campaign. Polling shows the race to be tight, and a Republican victory would be devastating to Democrats. A half hour later, polls close in Arkansas, where Democratic Sen. Mark Pryor is battling Republican Rep. Tom Cotton. Arkansas is one of several seats that the GOP has a chance of winning.
In this hour, we may begin to see the anti-incumbent mood spread to the states. Governors in five states -- Connecticut, Florida, Illinois, Maine and Pennsylvania -- are in danger of losing re-election. And we may see a Republican reclaim the governorship in deep blue Massachusetts, a position Mitt Romney once held.
9 p.m. ET: Voting will end in Kansas, a state Republicans should not have to be defending. Embattled Sen. Pat Roberts is trying to win a fourth term, but questions regarding his Kansas residency has put him on the political ropes. The twist in this race is that the Democratic candidate dropped out in order to give Independent Greg Orman a chance to win. It is unclear if Orman will align himself politically with Senate Democrats if he defeats Roberts, but it is one of the most intriguing contests of the night.
In South Dakota, it appears as if Republicans have turned around Gov. Mike Rounds' campaign -- a needed victory in their quest for six seats. Colorado is another seat Democrats need to win in order to maintain their majority, but Sen. Mark Udall is in danger of losing to GOP Rep. Cory Gardner.
The Louisiana Senate race features eight candidates, including Democratic Sen. Mary Landrieu -- and it is unlikely to be decided until the Dec. 6 runoff.
Davis' high profile, low polling bid to be the next Texas governor is likely to end in defeat. But the first legacy victory of the night is expected to happen when George P. Bush, son of Florida Gov. Jeb Bush, grandson of former President George H. W. Bush, nephew of former President George W. Bush, wins the race to become the next Texas Land Commissioner.
And we have another chance to see if the anti-incumbent mood is pulsating beyond the Beltway as four more governors in Colorado, Kansas, Michigan, and Wisconsin are in danger of losing re-election. Keep an eye on Wisconsin Gov. Scott Walker's race -- a defeat would all but end any plans he may have in running for the 2016 Republican presidential nomination.
10 p.m. ET: Republicans are expected to easily win the Montana Senate seat, and have a shot of picking up the Iowa Senate seat. Both seats are currently held by retiring Democrats. A loss in Montana is expected while a defeat in Iowa would be a major blow to the Democrat's ability to keep the Senate.
11 p.m. ET: Polls in the most populous state, California, close and Gov. Jerry Brown is expected to easily win re-election. Oregon begins releasing real vote totals and Democratic Sen. Jeff Merkley is expected to defeat GOP challenger Monica Wehby. Polls begin to close in Alaska.
1 a.m. ET: Voting ends in the U.S. as the final Alaska polls close. Depending on what happens earlier in the evening, the fate of the Senate majority may come down to who wins the competitive race between Democratic Sen. Mark Begich and GOP challenger Dan Sullivan.
CORRECTION: An earlier version of this story misstated who was the governor of Georgia.