Elections are taking place in the US on Tuesday - with people voting for who they want to see in Congress.
It's the part of the US government which makes the country's laws.
Normally, presidential elections are when we'd expect to see many famous people campaigning - but this time is different.
Rihanna, Justin Bieber, Ryan Reynolds and even Taylor Swift have been encouraging their followers to vote in the mid-terms.
Donald Trump's name is not on the ballot this time, unlike two years ago, but what happens on Tuesday could affect the rest of his presidency.
The House of Representatives and the Senate are both currently controlled by Trump's Republican party.
But there are seats the Democrats look like they could win - potentially limiting the laws President Trump can pass before 2020.
'I like her 25% less'
Taylor Swift shocked people last month when she came out in support of the Democrats ahead of the mid-term elections.
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I’m writing this post about the upcoming midterm elections on November 6th, in which I’ll be voting in the state of Tennessee. In the past I’ve been reluctant to publicly voice my political opinions, but due to several events in my life and in the world in the past two years, I feel very differently about that now. I always have and always will cast my vote based on which candidate will protect and fight for the human rights I believe we all deserve in this country. I believe in the fight for LGBTQ rights, and that any form of discrimination based on sexual orientation or gender is WRONG. I believe that the systemic racism we still see in this country towards people of color is terrifying, sickening and prevalent. I cannot vote for someone who will not be willing to fight for dignity for ALL Americans, no matter their skin color, gender or who they love. Running for Senate in the state of Tennessee is a woman named Marsha Blackburn. As much as I have in the past and would like to continue voting for women in office, I cannot support Marsha Blackburn. Her voting record in Congress appalls and terrifies me. She voted against equal pay for women. She voted against the Reauthorization of the Violence Against Women Act, which attempts to protect women from domestic violence, stalking, and date rape. She believes businesses have a right to refuse service to gay couples. She also believes they should not have the right to marry. These are not MY Tennessee values. I will be voting for Phil Bredesen for Senate and Jim Cooper for House of Representatives. Please, please educate yourself on the candidates running in your state and vote based on who most closely represents your values. For a lot of us, we may never find a candidate or party with whom we agree 100% on every issue, but we have to vote anyway. So many intelligent, thoughtful, self-possessed people have turned 18 in the past two years and now have the right and privilege to make their vote count. But first you need to register, which is quick and easy to do. October 9th is the LAST DAY to register to vote in the state of TN. Go to vote.org and you can find all the info. Happy Voting! 🗳😃🌈
It's the first time she has voiced her political views.
And while plenty of people were pleased that she'd encouraged her 112m Instagram followers to go out and vote, there were some who thought she was better sticking to music.
Donald Trump was one of them.
Lots of places reported a spike in voter registration following Taylor's post, but that also may have happened because it was the final day you could register to vote.
Unlike Taylor, Rihanna has been outspoken about politics - and her followers have been receiving regular reminders about the mid-terms.
The Fenty beauty boss is supporting Andrew Gillum to become Florida's governor, saying he's in favour of turning the minimum wage into a living wage, among other things.
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FLORIDA: You have the opportunity to make history this election. The US has only had four black Governors in its entire history, and we can help make #AndrewGillum the next one and Florida’s first! If you’re tired of feeling like you don’t matter in the political process, know the most important thing you can do in supporting a candidate is finding someone who will take on critical issues such as: making minimum wage a livable wage, paying teachers what their worth, ensuring criminal justice reform, making healthcare a right, and repealing Stand Your Ground. That’s a platform we MUST support. Let’s #bringithome, Florida. Vote @andrewgillum. And VOTE YES on Amendment 4 to restore voting rights to folks who have already paid their debt to society. VOTE on November 6th!
This is the first election in which Black-ish star Yara Shahidi is able to vote.
She created a campaign to "inspire the most powerful voting block in America" - young people - to vote with her.
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4 days until midterm elections dance ✨ Let’s show up in any and every way possible (shout out to all of the early voters) and remember that we vote for not only ourselves, but for “all of our sons and daughters” and every layer & intersection of identity ✨ we vote for each other 🗳#wevotenext
Young people haven't voted in big numbers in previous mid-term elections, which is perhaps why so many celebrities have chosen to campaign this time.
Some research suggests that more have registered to vote and are "looking forward" to the vote on 6 November.
But historically, turnout among young people is only around 20%.
Michael B Jordan is working to encourage voting among African-Americans, who he says "often feel like their vote doesn't matter".
The Black Panther star has been going door-to-door in Georgia to remind people about the election and show campaigners some love.
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I know some of you think your vote doesn’t matter, but your vote can help elect officials who can make a difference on police brutality, criminal justice reform, and racial justice. We have to do everything in our power to get our friends and families out to vote next Tuesday, November 6th. That's why I've been making surprise visits to Black voters doors with @VotingWhileBlack in Georgia. Text VOTE to 225568 and I’ll hit you up with a text to tell you more about how you can join me ✊🏾#VotingWhileBlack
Over in Texas, Travis Scott has been out trying to win support for Beto O'Rourke - who will become Texas's first Democratic senator in 24 years if he wins.
He supports free healthcare, wants cannabis legalised and has called for new gun control laws.
"All the kids, you just need to go out, hit these polls. We need to tell our peers to step out and vote... we can change the world," Travis said at a rally in Houston.
And we couldn't write this piece without mentioning Travis's mentor and kind-of brother-in-law, Kanye West.
The rapper has been the biggest celebrity story in politics this year, having ramped up his support for President Trump.
But his message has been a pretty confused one in recent weeks.
Kanye met Trump in the Oval Office early on in October to discuss prison reform, telling Trump during the meeting that he "loved" him.
Next came a $73,540 donation - around £56,000 - to a woman who is running to be mayor of his home city of Chicago and is backed by Democrat Chance the Rapper.
Most recently though, after being linked to a campaign called Blexit which encouraged black voters to quit the Democratic party, he says he's "distancing" himself from politics.
"I've been used," he wrote.
My eyes are now wide open and now realize I’ve been used to spread messages I don’t believe in. I am distancing myself from politics and completely focusing on being creative !!!— ye (@kanyewest) October 30, 2018
It's unclear whether he's talking about being used by Candace Owens, who ran the Blexit campaign, Trump, or somebody else.
His Twitter feed has a slightly different feel to it now.
McDonald’s is my favorite restaurant— ye (@kanyewest) November 4, 2018
From Blake Lively and Ryan Reynold to Justin Bieber, Oprah and Ariana Grande, most celebrities have had a more consistent message though - go out and vote.