House Democrats are bracing for losses on Election Day, but just how bad of a night will it be?

A few races will serve as cues throughout the evening, as polls close across the country. They will be harbingers for House Republicans, who are looking at gains anywhere from six to a dozen seats.

Here are the bellwether House races to watch as results come in, in order of poll closing times:

7 p.m.
Polls close in: Georgia, Indiana, Kentucky, New Hampshire, South Carolina, Vermont and Virginia
Bellwether race: New Hampshire’s 1st District
Rating: Tossup

Plenty of Democratic operatives are worried about Rep. Carol Shea-Porter’s re-election. But in a year when at least 15 House Democrats are in statistically tied races, she is considered slightly safer than some of her colleagues.

Most of all, her fate may be tied with Democratic Sen. Jeanne Shaheen’s performance against former Sen. Scott P. Brown, a Republican.

But if Shea-Porter goes down early on Tuesday, it’s likely plenty other House Democrats will be sweating bullets from coast-to-coast for the rest of the night.

7:30 p.m.
Polls close in: North Carolina, Ohio and West Virginia
Bellwether race: West Virginia’s 3rd District
Rating: Tossup

Nineteen-term Rep. Nick J. Rahall II, D-W.Va., faces his first dog fight in decades.

The triple-whammy of the Mountain State’s shift toward the Republican Party, GOP outside group spending against him and a rough Democratic climate could pull him under.

It’s remarkable Rahall, one of the remaining Blue Dog Democrats, has held on to this seat this long. He can thank his strong local brand for that boon.

But if he loses Tuesday night, it’s a sign the partisan shift could take down other long-serving Democrats like him, such as Rep. Collin C. Peterson of Minnesota.

8 p.m.
Polls close in: Alabama, Arkansas (8:30pm), Connecticut, Delaware, District of Columbia, Florida, Illinois, Maine, Maryland, Massachusetts, Michigan, Mississippi, Missouri, New Jersey, Oklahoma, Pennsylvania, Rhode Island, South Dakota, Tennessee and Texas
Bellwether race: Illinois’ 10th District
Rating: Tossup

This Chicagoland rematch between freshman Rep. Brad Schneider, D-Ill., and former Rep. Robert Dold, R-Ill., is one of the most contested in the country.

The district votes for Democrats in presidential elections by a double-digit margin. But the voters there have shown an independent streak further down the ballot, picking moderate House Republicans in this district north of Chicago.

Democrats have tried hard to paint Dold as a tea party extremist to make him unpalatable to the electorate. It’s a message national Democrats have also tried in a number of other competitive races in New Hampshire and California, hoping for similar results.

So if this race goes to Dold, it’s a bad sign for Democrats in other contested races across the country.

9 p.m.
Polls close in: Arizona, Colorado, Kansas, Louisiana, Minnesota, Nebraska, New Mexico, New York, Wisconsin and Wyoming
Bellwether race: Arizona’s 1st District
Rating: Tossup

Rep. Ann Kirkpatrick, D-Ariz., has a deft turnout operation and a lackluster challenger. In a neutral environment, she would likely even have breathing room on her march to re-election.

But if Kirkpatrick loses, it means that candidate and campaign quality are not overriding a bad climate for Democrats. Look for more to fall in the coming hours.

10 p.m.
Polls close in: Iowa, Montana, Nevada and Utah
Bellwether race: Iowa’s 2nd District
Rating: Leans Democratic

Two of Iowa’s House districts once thought to be safe bets for Democrats came into play in the final weeks of the cycle. It’s almost solely thanks to Rep. Bruce Braley’s sub-par performance as the Democratic nominee in the Hawkeye State’s open-seat Senate contest.

Braley’s downballot drag gives Republicans a chance to sweep the entire Iowa congressional delegation — an almost unfathomable outcome a couple months ago. It’s tough, but not impossible — and Rep. Dave Loebsack will be the toughest for Republicans to topple.

After all, Iowans rarely fire their members of Congress. The last incumbent to lose re-election in Iowa in a non member vs. member race was was Rep. Jim Leach, R-Iowa, who lost to Loebsack in the Democratic wave of 2006.

If Loebsack meets a similar fate in this district — which Obama carried by a 13-point margin — then a sweep of the delegation is a virtual lock.

11 p.m.
Polls close in: Alaska (12 a.m.), California, Hawaii (12 a.m.), Idaho, North Dakota, Oregon and Washington
Bellwether race: California’s 26th District
Rating: Leans Democratic

By the time polls close in California, a number of incumbents will already have lost. But if the 26th District slips away from Democrats, expect to see some rough returns for the party in the Golden State.

Obama carried this Ventura County-based district by a 10-point margin in 2012 — far larger than the other competitive districts in California, two of which made it into Roll Call’s list of the 10 most vulnerable House incumbents.

Freshman Rep. Julia Brownley, D-Calif., far outraised her GOP opponent for the race: state Assemblyman Jeff Gorell. And Gorell saw much less spending from GOP outside groups than the other California districts.

If Brownley can’t hold on, it’s hard to see how her fellow freshmen in the California delegation survive, too.

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