FACTBOX-The races that will decide control of the US Senate

Democrats need to pick up at least four seats ​in November's midterm elections to win control of the 100-seat US Senate, where Republicans currently hold a 53-47 majority. That was seen as unlikely at the beginning of the year, but President Donald ​Trump's unpopularity and voter frustrations over the Iran war and rising prices have made many races competitive even in states that he won ‌handily in 2024. Here are ​the races that will determine control of the Senate:

MAINE Democrats' top opportunity to pick up a seat is in Maine, the lone state where a Republican incumbent is up for reelection in a state Trump lost in 2024.

Republican Senator Susan Collins has distanced herself from Trump and declined to appear in the state with Vice President JD Vance. During a debate earlier this month, Collins — who voted to convict Trump after he was impeached following the January 6 insurrection — acknowledged that she isn't the president's favorite senator and said he won't be coming to Maine. Democrats say she only votes against Trump in the Senate when it doesn't matter — such as when she ‌voted against a sweeping tax-cut package last year after backing it in a procedural vote. Democrats hope voters will hold her accountable for helping confirm Brett Kavanaugh to the US Supreme Court, which led to the overturning of a federal right to abortion.

Democrats, however, have their own drama. The party's original nominee, progressive oysterman Graham Platner, was pressured into withdrawing following sexual assault allegations, forcing the state party to scramble for a new candidate. Platner has denied the allegations. Former Maine Senate President Troy Jackson, another progressive, emerged as Platner's replacement.

Jackson has nearly caught up to Collins on the fundraising front. He has raised $20.4 million so far, with $4 million unspent as of September 30, while Collins has raised $24 million, with $5.4 million still in the bank. Outside groups are spending heavily as well. AdImpact, a monitoring service, predicts they will spend a total of $199 million on this election — equal to $171 for every adult in the state.

Republican groups are outspending Democrats here, but most opinion polls ‌show Jackson holding a narrow lead. OHIO

Democrat Sherrod Brown is seeking to return to the Senate after losing his seat in 2024, and working-class frustration with the Iran war and rising prices may be giving him a tailwind. This time, Brown faces US Senator Jon Husted, who was appointed to the Senate to replace Vance when he left office for the White House.

The Ohio race has become one of the most expensive Senate contests ‌in the nation. AdImpact estimates Republican groups will spend $246 million on ads, while Democrats will spend $177 million. Brown has $16 million available for the final stretch, while Husted has $8.8 million. Recent polls show Brown leading by between 1 and 8 percentage points.

ALASKA Trump traveled to Alaska last week to shore up incumbent Republican Senator Dan Sullivan, who is facing a stiff challenge from Democrat Mary Peltola, a former US Representative.

Alaska allows voters to rank their top picks rather than choosing a single candidate. Voters will have four choices, including Sullivan, Peltola and another Dan Sullivan, a candidate Republicans have called a decoy in what they believe is a Democratic effort to confuse voters. Peltola has outraised Sullivan, but the Republican enters the final stretch of the campaign with $5.1 million in the bank, compared to $3.1 million for Peltola. Outside Republican groups have spent $33 million, while Democratic groups have spent $27 million.

Trump won Alaska by 13 points in 2024, but recent polls show Peltola leading or tied with Sullivan. TEXAS

No Democrat has won statewide in Texas since 1994. James Talarico, a state representative, could break the streak. Talarico faces a historically weak Republican nominee in Attorney General Ken Paxton, ⁠but Texas is still ​Texas — a big, conservative-leaning state that has dashed Democratic hopes repeatedly in recent years.

Trump won Texas by nearly 14 points in ⁠2024. Yet outside Republican groups have already spent a staggering $240 million to hold the seat after runoff voters nominated the scandal-plagued Paxton over incumbent Republican US Senator John Cornyn. Trump endorsed Paxton even though Cornyn was widely believed to have an easier path to victory. Leaked audio has exposed daylight between Trump and Paxton, who privately told donors that the president's midterm convention hurt his campaign.

Democratic groups have spent $50 million on this race, far less than Republicans. But Talarico's campaign has outraised Paxton's by $49 million and reported $16 million more in its campaign coffers as of ⁠September 30. Opinion polls show the race ranging from a tie to a 6-point Talarico lead.

IOWA Trump's unpopularity, tariffs and the Iran war have put Republicans on defense in Iowa, where Trump won by 13 points in 2024.

Republican US Senator Joni Ernst's decision not to seek reelection has made this an open-seat contest between Republican Representative Ashley Hinson and Democratic state Representative Josh Turek, a two-time Paralympic gold medalist. Hinson has called for an "immediate end" to the Iran war and said Iowans should not have to pay higher fuel ​or grocery prices as a result of it. However, she has repeatedly voted against resolutions in Congress calling for an end to the war.

Hinson has outraised Turek and had $6.9 million available to spend as of September 30, nearly three times what Turek has in his war chest. Outside Republican groups have spent $61 million to Democrats' $55 million. Recent polls show the race effectively tied.

MICHIGAN The Democratic establishment didn't get its ⁠pick in Michigan. Progressive outsider Abdul El-Sayed narrowly defeated moderate US Representative Haley Stevens during the primary, putting him on a collision course with Republican Mike Rogers, a former US Representative, in what could be the tightest race for a Democratic-held Senate seat this year.

Rogers has said Canada is not the United States' enemy, distancing himself from the president and his tariffs. Former Vice President Kamala Harris has campaigned with El-Sayed, and former President Barack Obama is set to rally with him later this month. The latest batch of polls shows El-Sayed leading by between 1 and 7 percentage ⁠points.

Republicans ​have spent $104 million in Michigan's Senate race, nearly double Democrats' $55 million. NEW HAMPSHIRE

Democrats are defending another open seat in New Hampshire, though this is a state Harris won by nearly 3 points in 2024. Democratic US Representative Chris Pappas is running against former US Senator John Sununu, who was ousted by Democrat Jeanne Shaheen in 2008. Shaheen is retiring.

Sununu benefits from a famous last name. His brother Chris was governor until last year and his father — also named John — was a governor and White House chief of staff for President George H.W. Bush. Republicans have outspent Democrats in this race, $30 million to $15.5 million.

Pappas has maintained a consistent polling lead of 5 to 8 points in recent surveys. GEORGIA

Incumbent Democratic Senator Jon Ossoff appears to be holding his own against a challenge from Republican Representative Mike Collins in Georgia, a state Trump won by 2 percentage points in 2024. Recent polls show Ossoff holding a double-digit lead, ⁠and some outside Republican groups have pulled out of the race. Ossoff holds a clear financial advantage. He has raised $98 million as of September 30, with $26.3 million still unspent. Collins, by contrast, has raised $11 million and has $1.1 million available.

NORTH CAROLINA Republicans appear to have conceded North Carolina, where outside spending groups have dropped their support significantly in recent weeks.

Opinion polls show former Democratic Governor Roy Cooper holding a steady lead over former Republican National ⁠Committee Chair Michael Whatley, a Trump ally. It's a pickup opportunity for Democrats, as Republican Senator Thom Tillis is not seeking reelection.

Cooper ⁠has raised $47.2 million, more than three times as much as his opponent, and has $12.5 million left to spend. Whatley has less than $1 million in the bank. Trump won North Carolina by 3 points in 2024.

KANSAS The political environment has shifted in favor of Democrats so much that Kansas is now in play. Republicans have diverted resources from North Carolina to shore up US Senator Roger Marshall, who in recent weeks has condemned the activity of Immigration and Customs Enforcement in his state.

Trump won Kansas by 16 points in 2024, but the state has twice elected Democratic Governor Laura Kelly. And Republican leaders have acknowledged the race is competitive and closer than they would ‌like it to be. Marshall's opponent is Adam Hamilton, founding pastor of a Methodist megachurch. ‌Marshall's campaign has outraised Hamilton's by $3 million and has nearly $1 million more unspent.

In a reversal of the usual pattern, Democratic groups have outspent Republicans here, $16 million to $11 million. Recent polls show Hamilton leading by between 1 and 3 percentage ​points.