On Tuesday, Americans head to the polls to vote for congressional representatives. Held every four years, halfway between presidential elections, midterms are "often a referendum on the president and party currently in power," J. Miles Coleman, election analyst with the University of Virginia Center for Politics, told DW. "The Republicans, as the minority party, are in about as good a position as they can be."

Democrats currently hold a slim majority in the House of Representatives (220-212, with three seats vacant), while the Senate is evenly divided, with 50 Democratic and 50 Republican lawmakers. Democratic Vice President Kamala Harris, as president of the Senate, acts as a tiebreaker when necessary.

Once voters head to the polls, this balance of power is likely to shift. All 435 seats in the House of Representatives and one-third of all Senate seats are up for grabs. In 36 states and three territories, the governorship and other key posts are on the ballot as well.

That's a lot to keep track of once returns start rolling in (even though it might take a while before final results are announced, especially in the close races). But don't worry ― DW has you covered.

Pennsylvania Senate race: Perennial swing state

Democrat John Fetterman and Republican Mehmet Oz, a famous TV personality, are vying for a seat that will be vacated by Republican incumbent Pat Toomey, who is not seeking reelection.

Democrats hoping to flip the seat have painted Oz as an outsider (he's from New Jersey) who doesn't care about Pennsylvania. Oz has focused his attacks on Fetterman's health.

The Democrat suffered a stroke in May, and while he says he is on the road to a full recovery, Fetterman's speech and hearing are still not back to 100%.

Pennsylvania, a key swing state, was decided by barely 1 percentage point in each of the last two presidential elections. At the moment, Fetterman and Oz are neck and neck. If the Democrats can pick up this seat, it will be an important win in the tight race for control of the Senate.

Georgia: High likelihood of a split ballot

After a close loss in 2018, Democrat Stacey Abrams is again trying to win the governorship in the southern state of Georgia. Abrams has been credited by newspapers like The New York Times and The Washington Post with boosting Democratic voter turnout in the 2020 presidential election and thus contributing to Joe Biden's narrow win over Donald Trump. Still, observers believe she will lose to sitting Republican Governor Brian Kemp again this year.

Nevertheless, many experts think voters are likely to split their ballot, pulling the lever for Republican Kemp in the gubernatorial race ― but for Democrat Raphael Warnock in his fight against former football star Herschel Walker, a Republican, in the race for the US Senate. Warnock, an incumbent, won his seat in a special election just two years ago.

In Georgia, if no candidate wins more than 50% in the first round of votes, there will be a runoff election. If this happens, and control of the Senate is down to Georgia just as it was two years ago, Americans would have to wait until December 6 to see whether Democrats or Republicans ultimately take the chamber.

Arizona gubernatorial race: Will an election denier take the reins?

In Arizona, Republican Kari Lake, a former television news anchor, is facing off against Democrat Katie Hobbs. The current Republican incumbent, Doug Ducey, cannot run again because of term limits. Lake is a vocal Trump supporter, and has said again and again that she believes the 2020 presidential election was stolen from him, a claim that has been thoroughly refuted.

Neither Lake nor Hobbs has managed to pull ahead in the close race. If Lake wins, Arizona — which was the site of a prolonged and bitter fight by election deniers to overturn the results of vote in 2020 — is likely to side with the Republican nominee for president in 2024, should there be questions surrounding results again.

Nevada Senate race: Economic issues take center stage

In 2016, Democrat Catherine Cortez Masto became the first Latina ever elected to the US Senate. Now, her seat is among those Democrats are most at risk of losing.

The economy is an extremely important issue for many voters this election cycl, and Nevada, which relies heavily on income generated by tourist magnets Las Vegas and Reno, has been particularly hard hit by the coronavirus pandemic.

Republicans hope voters are looking for a change in leadership and will vote for Adam Laxalt, whose father and grandfather both served in the Senate. Laxalt, too, was endorsed by Trump and is one of hundreds of Republican election deniers on the ballot this year.

Virginia House races: A potential bellwether

"For me, the question is not 'Who wins the House?' but how big the Republican majority will be," election analyst J. Miles Coleman told DW.

According to the political scientist, there are three US House districts ― all of which are currently held by Democrats ― whose early returns will be a good indicator for how the rest of the evening goes for Republicans.

Virginia's Second Congressional District has a large military population, and Biden only narrowly managed to win it in 2020. District 7, however, went to Biden by nearly seven percentage points in 2020.

"If Republicans pick up the Second District in these midterms, that's the bare minimum type of district they need to win a majority" in the House, Coleman said. If they win District 7, too, "they're probably on track for a good night."

And if Republicans take District 10, which Biden won by a whopping 18 points in 2020?

"Then," Coleman said, "they are going to have maybe their biggest majority in the House since World War II."