These 7 down-ballot races could determine control of Congress

All eyes are on the presidential election 10 days from now. But how effective either candidate will be will depend on whether they have the majorities in Congress necessary to pass their policies into law.

Both chambers of Congress are almost evenly divided, and a handful of results in favor of one party or another could give Democrats or Republicans a critical edge. NBC News recently identified several down-ballot races for both the House of Representatives and the U.S. Senate that could prove decisive in determining which party controls either chamber of Congress.

1. Texas' Senate race

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Sen. Ted Cruz (R-Texas) is currently battling for his political life against Rep. Colin Allred (D-Texas), who is raising large sums and polling within the margin of error according to FiveThirtyEight's aggregated polling data. Moreover, Texas has added roughly 2.5 million new voters to its rolls since 2018, when Cruz barely defeated then-Rep. Beto O'Rourke (D-Texas) by less than three percentage points statewide. Allred has seized on Texas' draconian abortion ban as a central campaign theme, pointing out that Cruz has voted multiple times to ban abortion — even without exceptions for rape and incest.

2. Nebraska's Senate race

One surprisingly close race is in the Cornhusker State, where Sen. Deb Fischer (R-Nebraska) is in a tight reelection contest against union organizer Dan Osborn, who is running as an independent rather than as a Democrat. Polls are neck-and-neck, showing either Osborn or Fischer ahead depending on which candidate sponsored the poll.

Republicans currently only need to flip two seats to win back the Senate majority. One of those flips is almost certainly to come from West Virginia, where the deep-red state's open Senate seat will likely go to Republican Governor Jim Justice. the other flip could come from red states like Montana and Ohio, where Democratic incumbents are running for reelection. But if Fischer loses, the GOP taking back control of the Senate could become much less likely.

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3. Maryland's Senate race

Even though Maryland is considered a safe blue state, its open Senate seat is getting national attention due to Democrat Angela Alsobrooks facing off with popular two-term Republican governor Larry Hogan. The former governor has attempted to set himself apart from the rest of the GOP by being a vocal critic of former President Donald Trump. But the race is still considered to be less competitive than Texas and Nebraska, with Alsobrooks regularly posting double-digit leads over Hogan. Additionally, a recent report found that Hogan directed millions of dollars in state funds to his real estate clients while he was in office.

4. Florida's Senate race

In the Sunshine State, former Rep. Debbie Mucarsel-Powell (D-Florida) has mounted a surprisingly competitive challenge to Sen. Rick Scott (R-Florida). FiveThirtyEight shows Scott leading Mucarsel-Powell by anywhere from two to eight percentage points in polls, and Florida has roughly one million more registered Republicans than Democrats. Still, the race is noteworthy given that Floridians are also voting on whether to enshrine abortion rights in their state constitution in November. Abortion-related ballot measures are undefeated in favor of preserving reproductive rights ever since the Supreme Court overturned Roe v. Wade in 2022 — even in deep-red states like Kansas, Kentucky and Montana.

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5. Pennsylvania's 10th Congressional District race

Rep. Scott Perry (R-Pennsylvania), who is the former chairman of the far-right House Freedom Caucus, could be ousted next month given the latest polls. According to FiveThirtyEight, former TV news anchor Janelle Stelson is pulling ahead in the latest polls of 10th district voters. NBC News reported that the Cook Political Report has recently re-designated the district from "lean Republican" to "toss-up" amid Stelson's October momentum.

6. Virginia's 2nd Congressional District race

The House majority could also flip depending on how Rep. Jen Kiggans (R-Virginia) fares in her battle for a second term. Her Democratic opponent, Missy Cotter Smasal, is polling within the margin of error. But another reason to keep an eye on the Old Dominion State is that it will be among the first states to announce winners on November 5, and Kiggans' race could be a bellwether to predict how Republicans overall will fare in the election.

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7. Wisconsin's 3rd Congressional District race

Rep. Derrick Van Orden (R-Wisconsin), who is running for a second term, represents a rural district in the Badger State. Polls show that he's in a virtual tie with Democrat Rebecca Cooke, who is running as a moderate. Van Orden has attracted negative attention to himself for swearing at teenaged Senate pages and for reportedly holding drunken parties in his House office. Turnout in the district could be relatively higher than normal given Wisconsin's importance as one of the three critically important Blue Wall states, along with Michigan and Pennsylvania.

Currently, House Speaker Mike Johnson can only afford two defections from his conference in order to pass legislation through the House. His already tenuous majority has steadily weakened with multiple Republican incumbents — including those from safe Republican districts — announcing their retirements in 2024. Democrats could take back the majority by flipping five seats.

Click here to read NBC's report in its entirety.