Senate Democrats head into Tuesday’s elections facing the fight of their lives: defending a 51-49 majority with a formidable map that Republicans call the best opportunity to gain ground in a decade.

Republicans have already cut that to nearly 50-50, with West Virginia Sen. Joe Manchin, an independent who caucuses with Democrats, retiring and assurances that GOP Gov. Jim Justice will likely get him in one of the reddest states in the United States. country.

Now, Democrats basically need to draw a straight flush to keep themselves in the majority; They rely on a few battle-hardened incumbents and members of the House of Representatives to hold red and purple state seats in their respective columns, while also considering an extremely small lineup that is extremely difficult to win. Turn opportunities.

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And even if they manage to defend all blue seats, Democrats could still find themselves in the minority if former President Donald Trump defeats Vice President Kamala Harris and vice presidential candidate J.D. Vance becomes the GOP tiebreaker.

Here are five Senate races to watch on Tuesday that will help determine control of the Senate and some of the races in which Democrats are on the offensive.

Montana

Three-term incumbent Democratic Sen. Jon Tester has managed to emerge from tight races before despite running in a hostile district. But his race for a fourth term may be his toughest challenge yet.

Tester is running against businessman and former Navy SEAL Tim Sheehy, a wealthy candidate highly sought after by Senate GOP Leader Mitch McConnell and Sen. Steve Daines, who heads the Senate Republicans’ campaign arm and has made it his mission to unseat Tester. fellow Montanan.

The polls are daunting for Tester; More than 5 points behind Average vote of 538and has not led in the measurement since July 9.

Tester relied on his authenticity as a seven-fingered farmer and third-generation Montanan to argue that he heard his constituents’ concerns and was fighting for them. He also hopes an abortion referendum on the ballot would help increase turnout among Democrats.

Sheehy, meanwhile, ran as a businessman who accused Tester of being out of touch with the increasingly Republican state and of Washington being dysfunctional overall. He faced a number of attacks from Tester, including how he suffered a gunshot wound to his forearm and the fact that he was not originally from Montana; This was a state that had long prioritized a sense of place, but increasingly the rich were coming from abroad. statists buy land.

Yet Tester is thought to face formidable challenges despite his past successful high-wire acts. Trump won the state by more than 16 points in 2020, and while Tester is expected to be ahead of Harris, such a lead could be insurmountable for the incumbent senator.

Unless Democrats can take the GOP-held seat, a Tester loss would likely give Republicans the Senate majority.

Ohio

Democratic Sen. Sherrod Brown is also running for his fourth term in the state, which has flipped from purple to red and jeopardizes his re-election chances.

Brown is running as a blue-collar populist, with a gravelly voice and often wearing a rumpled suit that highlights the good intentions of ordinary men. Brown, a union supporter and opponent of some international trade agreements before he became cool, has consistently outperformed white voters without college degrees who used to vote Democratic but have defected en masse to Trump.

He has also focused heavily on abortion, after 57% of Ohioans supported a referendum last year protecting access to the procedure. He has also run ads showing support for law enforcement as a way to differentiate himself from the national Democrats’ brand.

Brown is facing Bernie Moreno, a Colombian immigrant and businessman. Moreno worked hard and spent millions to make Brown seem too liberal for a state that twice nominated Trump by 8 points. He himself has focused on social issues such as abortion and transgender athletes participating in women’s sports.

Moreno never led 538 voting averagebut he has significantly chipped away at Brown’s advantage and is now just 1.2 points behind after trailing by 6.5 points at the end of July. Moreno has gained support from a series of outside spending efforts from Republicans in Washington who want to win as large a majority as possible, especially as Montana becomes increasingly inaccessible to Democrats.

Here too, the presidential margin is expected to play an important role. Like Tester, Brown is expected to move ahead of Harris. But Brown could face serious repercussions if Trump widens his margin of victory for a third time.

Michigan

The retirement of Democratic Sen. Debbie Stabenow has created a huge opportunity for Republicans to fill the void in the purple state.

The race pits Democratic Rep. Elissa Slotkin against former GOP Rep. Mike Rogers. Slotkin has a 3.5 point lead Average vote of 538Besides the fundraising advantage, the lack of an incumbent makes the race particularly appetizing for Republicans.

Slotkin relied on his background as a CIA analyst serving in Iraq, Rogers’ votes against abortion protections, and his crossover appeal, including support from former Rep. Liz Cheney.

Rogers, meanwhile, has embraced Trump after past criticism and attacked Slotkin over concerns about transgender athletes and electric vehicle production (Slotkin repeats that he lives on a dirt road but wants the “next generation” of vehicles to be made in the state).

A big X-factor in both the presidential and Senate races in the state is the war in Gaza, which has infuriated Michigan’s significant Arab population and left voters disgruntled and disgruntled with President Joe Biden and Democratic candidates this year.

Pennsylvania

Three-term Democratic Senator Bob Casey is a fixture in Pennsylvania; His father was a former governor, and Casey’s name is heard all over the state.

But he will face a strong opponent in Dave McCormick, a former hedge fund manager who has been heavily recruited this year. He ran in 2022 but was defeated by Dr. in the GOP primary. He lost to Mehmet Öz. Oz has now lost to Sen. John FettermanD.

Pennsylvania is home to fierce and competitive presidential contests, and the Senate race is no different. Casey leads by 2.6 points 538 voting averageHowever, there has been a decline since the 8-point gap in August.

Casey and Democrats attacked McCormick for her abortion, her Connecticut residence and past business ties to China. McCormick, meanwhile, embraced Trump after butting heads with him after endorsing Oz in 2022 and pushed voters Tuesday to “make a change” by accusing Casey of being out of touch with Pennsylvanians and too entrenched in Washington.

Arizona

Independent Senator Kyrsten Sinema, who meets with Democrats, created an important opportunity for Republicans by announcing in March that she would not run for a second term.

But Kari Lake, the unsuccessful 2022 gubernatorial candidate and this year’s GOP Senate candidate, is in dire straits.

Democratic Rep. Ruben Gallego leads steadily Average vote of 538 Even if Trump is thought to have a presidential-level edge in the state.

The race represents a rare case where low name recognition is advantageous, especially in a state that values ​​pragmatism like Arizona.

Gallego has an extensive history as a progressive, but he wasn’t a well-known legislator outside his district, offering him a chance to rebrand himself as a moderate, including supporting things like increased border enforcement after Trump nailed his border wall.

Lake, meanwhile, became a MAGA rock star in 2022 after specifically criticizing “McCain Republicans” and refusing to concede his defeat in that year’s governor’s race. He has tried to moderate this year, including reaching out to former Gov. Doug Ducey, but he has a more firebrand image than Gallego, making it difficult to appeal to centrists in and around Phoenix who hold the key to victory in Arizona. .

He still has not accepted the results of the 2022 race or Trump’s 2020 defeat.

The race could offer important clues about how Democrats can keep Latino voters in their column this year in the face of widespread defection concerns. Gallego, who is of Colombian and Mexican descent and a war veteran, said he has spoken to Latino voters who say they would support both him and Trump.

The race will also serve as a barometer of sorts for the Senate overall. Republicans will rue the missed opportunity if Gallego wins, but if Lake can pull off a victory, it likely means Republicans are having a good night elsewhere, too.

Democrats’ offensive opportunities

Democrats are playing in a small number of Republican-held seats, but they face major challenges in flipping any of them.

GOP Sens. Ted Cruz of Texas and Rick Scott of Florida are facing Rep. Colin Allred and former Rep. Debbie Mucarsel-Powell, respectively. FiveThirtyEight’s polling averages show both Democrats in very close proximity, and the national party is starting to spend money there, especially in Texas. But both red states are difficult areas for Democrats to gain ground, especially in a presidential year.

Independent Dan Osborn is also challenging GOP Sen. Deb Fischer in Nebraska. Osborn has insisted he will not caucus with any party in the Senate, but Republicans have worked hard to paint him as a Democrat masquerading as a centrist. Polls point to a tight race, but Osborn also faces headwinds in a heavily Republican-leaning state.