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All eyes will be on the U.S. Senate in 2018 with several key seats up for grabs in the midterm elections.
USA TODAY

WASHINGTON — Buckle up for a dramatic, vicious, multibillion-dollar fight for control of the Senate next year, which may end with almost no changes to the chamber’s narrow partisan divide.

It’s not for lack of opportunity: 33 senators are up for re-election in 2018, including 23 Democrats, two independents who caucus with Democrats, and eight Republicans.

But only about a dozen of those contests will be competitive. And two competing crosscurrents of this election — an unpopular Republican in the White House versus an electoral map that puts Democrats at a major disadvantage — could cancel each other out.

Republicans are defending far fewer seats, and only two GOP senators are considered truly vulnerable: Sens. Jeff Flake of Arizona and Dean Heller of Nevada. Meanwhile, 10 Senate Democrats are up for-election in states that Trump won in 2016, and they all have targets plastered on their backs.

Blowing in the other direction? History. The party that controls the White House almost always loses seats in Congress during midterm elections. President Trump, whose public approval ratings are below 40%, is expected to be a particularly heavy drag on the GOP in 2018.

Democrats would need to pick up three seats to retake control of the Senate, which analysts say is highly unlikely. Republicans would need a net gain of eight seats to hit the coveted 60-vote threshold to break a filibuster, which political experts say is equally far-fetched.

Of course, the political climate could change dramatically between now and November 2018, resulting in major shifts in the Senate’s current 52-48 partisan balance. And there’s no question that both parties — and their special-interest allies — will mount a pricey, pitched battle to sway the outcome.

Here’s a race-by-race look at the key contests we’re watching, with ratings from Inside Elections, which provides nonpartisan analysis and research. “Tossup” indicates the race is dead even; “tilt” ratings indicate a slight edge for the specified party; and “lean” ratings indicate a definite edge, but still an uncertain outcome.

Arizona

Incumbent: Republican Jeff Flake
Inside Elections rating: Tilt Republican
2016 presidential election results: Trump: 49%, Clinton: 45%