Polls will soon open across the country with dozens of Senate and gubernatorial races up for grabs, as well as up to 100 competitive U.S. House contests.

With so many races – and control of the House and Senate – in the balance, it is hard to know where to look on election night.

Here is an hour-by-hour guide (all times Eastern) to the vote tallies that will serve as leading indicators for where the election is headed.

7 p.m.: Indiana and Kentucky

There are three House races in the Hoosier State that will tell us what kind of night it will be for Democrats. The 8th District open seat appears a certain pickup for Republican Larry Bucshon of Evansville, while the 9th District fight between Democratic Rep. Baron Hill and Republican lawyer Todd Young is a jump ball. Democratic Rep. Joe Donnelly is favored in the South Bend-based 2nd District.

If Democrats lose just one of those three, they can hold the House. Lose two, and their majority likely is gone. Lose all three, and Republicans will gain upward of 60 seats.

In Kentucky, Republicans are spending money on semi-long-shot challenger Andy Barr in the 6th District race against Democratic Rep. Ben Chandler. If Chandler loses, Republicans could well make a historic number of pickups.

Meanwhile, in the Senate race, if state Attorney General Jack Conway, a Democrat, can defeat ophthalmologist Rand Paul, a Republican, it would be a major upset.

7:30 p.m.: Ohio and West Virginia

Democratic Ohio Gov. Ted Strickland is in political peril in his race against former GOP Rep. John Kasich. The White House would love to see Strickland win because controlling the governor’s mansion in a state likely to be competitive in 2012 could give President Obama a leg up.

West Virginia Gov. Joe Manchin, a Democrat, appears to have stabilized his bid for the state’s open Senate seat. But Obama and the national Democratic Party are unpopular in the Mountain State, and that could drag Republican businessman John Raese across the finish line.

8 p.m.: Florida

The marquee governor’s race of the night is between state Chief Financial Officer Alex Sink, a Democrat, and former health care executive Rick Scott, a Republican. Both parties have dumped scads of money into the state, and Democrats see this outcome as crucial to their entire night. Also keep an eye on the south Florida 25th District open seat race, a rare opportunity for a Democratic pickup.

9 p.m.: Colorado and South Dakota

No race has seen more spending by outside groups – $25 million and counting – than the matchup between appointed Democratic Sen. Michael Bennet and Weld County Prosecutor Ken Buck, a Republican. Buck has tried to make the contest a referendum on the president, but he has made enough verbal gaffes to give Bennet a path to victory.

South Dakota has only one congressional district, but it is playing host to one of the best races nationwide between Democratic Rep. Stephanie Herseth Sandlin and Republican state Rep. Kristi Noem. The race will serve as a test case for whether moderate Democrats can escape the drag of the national party.

10 p.m.: Nevada

The Senate race between Majority Leader Harry Reid and former state Assemblywoman Sharron Angle, a Republican, is on course to top $50 million in spending – a remarkable sum given how few voters are genuinely undecided in the contest. Both sides see symbolic importance in this race: a Democratic win would salvage what could be a tough night, while a Republican victory would mark the second time in four cycles the party had beaten the Democratic Senate leader.

11 p.m.: Oregon and Washington state

The race between Democratic Sen. Patty Murray and former state Sen. Dino Rossi, a Republican, in Washington has been tightening recently, but Murray remains well liked among the electorate. Rossi is trying to paint Murray as an insider, a potentially potent message in an anti-incumbent year.

In Oregon, former NBA player Chris Dudley, a Republican, has run a strong campaign and is in a nip-and-tuck race with former Democratic Gov. John Kitzhaber.