Trump, AOC and McConnell: the personalities that could determine who wins the Senate in 2020

WASHINGTON – The bruising campaign for the White House between President Donald Trump and his Democratic challenger will take center stage in 2020 but it's the contest for control of the Senate that will determine the presidential winner's ability to pass legislation, appoint judges and fund priorities.

Democrats, who effectively control 47 seats, need to flip at least four Republican Senate seats to recapture the upper chamber – or three if they win back the White House since the vice president breaks ties.

Republicans hold 23 of the 35 seats up for grabs next year, giving Democrats nearly twice as many pick-up opportunities. Adding to the Democrats' optimism is that many of the races are in states where the president's approval rating sits well under 50%.

Republicans counter that all but two (Colorado and Maine) of the GOP seats up for election are in states Trump won in 2016. And the two most vulnerable Democrats are in states (Alabama and Michigan) that Trump won.

Thirteen months out from Election Day, there remains plenty of questions: Will primary voters nominate moderates or party reactionaries that would have a tougher time winning a general election? How will the the Democratic presidential nominee influence down-ballot Senate races? What kind of effect will congressional Democrats' pursuit of Trump's impeachment have on voters?

“So many things we don’t know," said Jennifer Duffy, a long-time Senate analyst with the non-partisan Cook Political Report.

Duffy and others watching 2020 elections give Democrats less than a 50-50 chance of recapturing the Senate considering there are only a handful of states in play right now.

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Already the attack ads have been launched by both parties.

Republicans are painting Democratic candidates as socialists who back far-left policies such as "Medicare for All," free college tuition and radical climate change remedies like the Green New Deal. They've begun airing ads in some states that feature Rep. Alexandria Ocasio-Cortez, the freshman New York Democrat and social media star who embodies the party's left-wing ideology.

Democrats are portraying Republicans as climate deniers and anti-immigration zealots who blindly back Trump. They've started airing ads with Senate Majority Leader Mitch McConnell, the Kentucky Republican whom opponents accuse of protecting Trump and obstructing important legislation from even getting a floor vote.

There is a soundness to each side's partisan strategy: In 2016, every Senate seat up for election was won by the party whose presidential nominee also captured that state.

Here's a look at the states in play and the chances the Senate could flip back to Democrats:

Republicans in Blue States

The two Republicans who represent states that Hillary Clinton captured in 2016 – Cory Gardner in Colorado and Susan Collins in Maine – are top targets for Democrats next year.

As a freshman senator who squeaked in five years ago, Gardner is considered more vulnerable than Collins, who won her fourth term in 2014 with 68% of the vote.

Former Colorado Gov. John Hickenlooper's entry into the race gives Democrats a formidable challenger with high name recognition in a state where Democrats will try to capitalize on issues such as climate change and health care.

But Republicans say Hickenlooper's shaky performance during a short stint as a 2020 presidential candidate and an expected primary challenge from former state House Speaker Andrew Romanoff may wound him in the general election.

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Collins' long-held image as a moderate voice on Capitol Hill took on water last year with her pivotal vote to confirm Brett Kavanaugh to the Supreme Court. Progressives fumed over her vote, promising to raise money and turn out Mainers to keep her from winning a fifth term.

Collins was leading her likely Democratic opponent, state House Speaker Sara Gideon, by double digits in a Gravis Marketing poll released in June. But there was a potential warning sign for the incumbent: the same poll found 48% approved of Collins' performance – the same percentage that disapproved.

The Republicans facing tough re-election battles

Few GOP incumbents have a bigger bullseye than Sen. Martha McSally in Arizona.

The former Air Force fighter pilot has a stellar resume but she is running in an increasingly purple state against a well-funded and high-profile challenger: former astronaut Mark Kelly, the husband of former congresswoman and gun-control advocate Gabby Giffords.

Kelly is a first-time candidate and Republican strategists said they hope to exploit that lack of experience on the campaign trail. McSally has never won statewide (she lost a Senate race in 2018 and was appointed to fill the vacancy created by John McCain's death last year). But she wields the power of incumbency and Trump's endorsement could turn out conservative Arizonans wary of McSally.

Democrats are optimistic they can flip the seats of two other Republican incumbents – Thom Tillis of North Carolina and Joni Ernst of Iowa.

Of the two, Tillis is in deeper peril, according to political experts, partly because there are signs the state might not be as red as it was in 2016. A Charlotte-area congressional seat that Trump won by 12 points in 2016 barely went for a Trump-endorsed Republican in a special election earlier this year.

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The vulnerable Democrats

Just as Republicans Gardner and Collins must find cross-over appeal in states that voted in 2016 for Clinton, Democrats Doug Jones (Alabama) and Gary Peters (Michigan) face a similar challenge because they're running for reelection in states that Trump won.

Jones is considered the most vulnerable incumbent running in 2020 – Democrat or Republican – chiefly because he represents a state that Trump carried by nearly 28 percentage points. Jones, the only Senate Democrat in the Deep South, came to the Senate after winning a closely contested special election in 2017 over Republican Roy Moore, who was tainted by allegations he had romantically pursued and sexually assaulted teenage girls when he was in his 30s.

Moore is running again but so are other Republicans, including Congressman Bradley Byrne and former Auburn Football Coach Tommy Tuberville, neither of whom carry the political baggage that helped Jones win his seat.

Republicans also believe that Peters is very beatable, largely because many Michiganders don't know him or aren't sure what to make of him. Polls show more than a third of state voters don't have a firm opinion of him despite nearly five years in office.

Peters is "weak" Duffy said. "It’s not that he has angered voters. It’s that they have no idea who he is.”

Republicans are also optimistic because GOP businessman and Army veteran John James, who outperformed expectations in a 2018 loss to Democratic Sen. Debbie Stabinow, has entered the race.

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The open seats

A senator's decision not to seek reelection presents a rare opportunity for opposing parties because it traditionally provides a better chance to flip a seat when there's no incumbent touting years of constituent achievement or legislative accomplishment.

But none of the four open seats – three GOP states (Georgia, Kansas and Tennessee) and one Democratic (New Mexico) – are in much danger of changing party control, according to political analysts.

Traditionally red Kansas could be the exception if Republican Kris Kobach wins the primary. The immigration hard-liner who lost a gubernatorial contest to Democrat Laura Kelly in 2018 is seen by analysts and political operatives on both sides as a weak candidate who would likely put the state in play if he wins the GOP nomination next year.

Georgia's open seat (created by the early retirement of Republican Johnny Isakson) will be paired with Republican David Perdue's reelection bid. That would give Democrats two chances to pick up a seat in a Deep South state that's been trending more purple recently. But chances of winning one of those were hurt when rising Democratic star Stacy Abrams opted not to run.

This article originally appeared on USA TODAY: 2020 Senate races may determine whether Democrats, GOP gain majority