Republican senator Dan S Sullivan is vying for re-election against Democrat Mary Peltola – and another candidate called Dan J Sullivan

Donald Trump has encouraged Alaskans to vote for the “real” Dan Sullivan, as he sought a breakthrough for the Republican incumbent senator in a tightly fought Senate race complicated by a rival candidate with a near-identical name.

Sullivan’s re-election campaign this year against Democrat Mary Peltola, a former US House lawmaker, has turned into one of the most hotly contested battles of the midterm elections, in which Democrats are hoping to seize back control of Congress and hamper Trump for the final two years of his presidency.

Democrat in Congress since 1983 rebuked over ‘dangerous’ campaign ad – will it harm her chances in tight Ohio race?

Last month, Marcy Kaptur, the longest-serving woman in congressional history, released a video advertisement in which she looks directly at the camera and says exactly what she thinks about one of the most divisive issues facing Democrats today.

“Here’s the truth: I voted with Republicans to keep transgender ideology out of our schools because parents know what’s best for their kids,” Kaptur says, “and boys should not play in girls’ sports.”

Ohio former senator attacks Republican rival as the ‘face of datacenters’ as he wraps AI concerns into pro-worker message

• Send us your questions on how the US economy is shaping the midterm elections

Sherrod Brown, the Democratic former senator from Ohio hoping to return to office in November’s midterm elections, has spent the past year traveling across his home state explaining to voters about all the ways the “system is rigged” against them. Recently, he’s been telling people about a trip he took across the north-west Ohio countryside.

“You’re driving on what looks like really good farmland, driving past fields, driving past barns, driving past milking parlors, and you see, all of a sudden, you see these huge cranes and you see these trucks coming,” Brown told a crowd of dozens at a coffee shop in the city of Lima earlier this month.

Polls show GOP candidates trailing Democrats in Senate races, and Republicans also struggling in House contests

Thirty days remain until the midterm elections, and Donald Trump and his Republican allies are pulling out all the stops to maintain control of Congress.

Super Pacs aligned with the GOP have already spent hundreds of millions of dollars on advertising and voter outreach in races expected to decide the majorities in the Senate and House of Representatives, and plan to spend even more before the election is over. The president, Vice-President JD Vance, and other top Republicans are fanning out across the country to stump for vulnerable lawmakers.

These graphics explain what the Democrats would need to do to flip the Senate and House of Representatives

A turning point in Donald Trump’s second term will soon arrive. On 3 November, voters across the US will decide whether to keep the president’s Republican allies in control of Congress, or return Democrats to the majority.

Many indicators of voter sentiment suggest the Democrats are favored to take back control of the House of Representatives, and potentially the Senate. Winning either would be a significant victory for the party and give it the power to block Trump’s legislative agenda and more aggressively investigate his administration.