One usually surefire way to gauge the political climate on election night is to follow the clock of poll closings across the nation, east to west.
But this is no normal midterm. Several races are expected to be razor-close to the very end, and some are all but certainly headed to runoffs or recounts.
"Election night might be more about looking for clues than getting answers," wrote Jennifer Duffy of the nonpartisan Cook Political Report. "Settle in for a long night, and prepare for the battle for the Senate majority to go into overtime."
That said, here's a rough schedule of the evening's events, in Pacific time, with thanks to Cook analysts.
4 p.m.: Polls close in key states, but the one to watch is New Hampshire, where Democratic Sen. Jeanne Shaheen is in a close race against Republican Scott Brown. Kentucky's contest between Senate Minority Leader Mitch McConnell and Democratic newcomer Alison Lundergan Grimes is also expected to be close, and Georgia may go to a runoff. So look to the Granite State for a first key test for Democrats in the battle for control of the Senate.
4:30 p.m.: The next big Senate showdown is in North Carolina, and if Democratic Sen. Kay Hagan holds on, that could provide a road map for the Senate battles ahead. Another assessment of the political landscape may be found in West Virginia, where Democratic Rep. Nick J. Rahall II is in the fight of his life for a 20th term.
5 p.m.: It's all about the governors -- Florida, Massachusetts and Maine all have tough contests. But the House races may prove just as interesting if an openly gay Republican beats a Democrat in Massachusetts' open 6th District. Also, keep a lookout to see if Republican Rep. Steve Southerland withstands a Democratic challenge in Florida.
5:30 p.m.: All eyes on Arkansas, as the state is poised to join its Southern neighbors in the red column in races for Senate and governor. Or not.
6 p.m.: Polls close in Louisiana, but with the three-way Senate race there expected to go to a runoff, perhaps better to focus on Kansas, Colorado and Wisconsin. Governors in all three states are on the ballot -- and voter reaction to Republican incumbents Scott Walker in Wisconsin and Sam Brownback in Kansas could provide insight into the mood. Colorado's Senate race between Democratic Sen. Mark Udall and Republican Cory Gardner could be decisive in determining which party controls the chamber, and intrigue surrounds the Kansas race between Republican Sen. Pat Roberts and newcomer Greg Orman, who has not said which party he would caucus with. Also interesting will be the House races in New York, where several Republicans are favored. And don't forget the three-way battle for an open Senate seat in South Dakota.
7 p.m.: If the Iowa Senate race results are taking too long to call, check out the Las Vegas-area House race, where Democratic Rep. Steven Horsford is in a late-emerging struggle for reelection in Nevada.
8 p.m.: West Coast polls close, with attention on several House races in California, where incumbents from both parties are in tough battles.
10 p.m.: Hello, Alaska. The so-close race between Democratic Sen. Mark Begich and Republican Dan Sullivan may not be decided even at this late hour. Think far-flung-ballot counting into the days ahead.