Technically, there are 469 races for the House and Senate this year, but we’ve boiled down that list to a trio of races to watch in each of eight regions across the country.
From vulnerable incumbents to competitive open seats to intra-party squabbles, the batch of races has a little of everything and can be a useful guide to track the trajectory of the election cycle in the months ahead.
New England: The race between Kelly Ayotte and Maggie Hassan could determine which party controls the Senate in the next Congress.
Mid-Atlantic states: Another race that could be critical in the battle for Senate control looks like a three-way race between two Democrats and a Republican incumbent.
The South: Florida is not only a presidential battleground but key Senate and House races are being waged there, too.
The Midwest: The rematch of the 2010 Senate race in Wisconsin looks to be just as competitive while the Democrats' preferred candidate for Senate in Ohio must endure millions of dollars in attack ads.
The Plains states: Sen. Roy Blunt isn't expected to lose his re-election bid for his Senate seat, but if things go south for him, it could be an indication of how things will go where Republicans are defending their seats.
The Mountain states: Republicans have struggled to come up with a candidate to challenge Sen. Michael Bennet, who just months ago appeared vulnerable.
The Southwest: An open-seat headache for Democrats has attracted a crowded Republican primary field.
The West: Rep. Joe Heck's run for Harry Reid's Senate seat creates a top takeover target for Democrats for his House seat.
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