House Majority Whip Jim Clyburn (D-S.C.) said on ABC's "This Week" Sunday that Sen. Bernie Sanders' identification as a democratic socialist may be an "extra burden" in down-ballot House races if he were to win the Democratic nomination.

Why it matters: Clyburn's comments echo fears from many establishment Democrats, who worry the House majority they won in 2018 by taking moderate seats carried by President Trump could be at risk with Sanders at the top of the ticket.

White House national security adviser Robert O'Brien repeatedly rejected on ABC's "This Week" an assessment from a congressional briefing led by the Office of the Director of National Intelligence that Russia is interfering in the 2020 election to help President Trump get re-elected.

Why it matters: The report put the Trump administration under fresh scrutiny in regard to steps it has been taking to combat the kind of interference that the U.S. encountered in 2016.

Sen. Bernie Sanders is projected to handily win the Nevada Democratic caucuses, becoming the clear frontrunner among 2020 Democratic presidential primary election candidates.

Why it matters: Nevada is the first state with a diverse population to hold a nominating contest, highlighting candidates' abilities to connect with voters of color — particularly Latino voters.

Michael Bloomberg, Bernie Sanders and Joe Biden — all close to 80 — are pushing the boundaries on social media, while their younger Democratic presidential rivals are comparatively staying out of the fray.

The big picture: President Trump's unexpected rise to political power has shown Democrats and world leaders the power of harnessing popular internet culture to get elected.

Sen. Bernie Sanders hailed his grassroots movement on Saturday evening as "unstoppable" after he was projected to win the Nevada Democratic primary caucus.

The big picture: Nevada, a state with a diverse population, was the first real test of how candidates could connect with people of color. Sanders tweeted: "Our multiracial, multigenerational movement is not only going to win in Nevada. It is going to sweep this country." His 2020 rivals gave mixed reactions as results poured in.

Andrew Yang referenced his departure from the 2020 race as he suggested on CNN Saturday narrowing the Democratic field, saying: "Someone needs to pull an Andrew Yang and be like, 'I've done the math, I'm not going to win.'"

Details: Yang said after Sen. Bernie Sanders was projected to win the Nevada caucus, "The rest of the field needs to consolidate, ideally." He noted "each candidate wants to be the last person standing to absorb the non-Bernie energy." But he added Sanders is "unlikely to get an outright majority of delegates heading into the convention, which is going to set the stage for the superdelegates to emerge, and then you're looking at a contested convention."

Go deeper: 2020 presidential election: Track the candidates

Sen. Elizabeth Warren's campaign said on Saturday it raised $14 million in the 10 days after the New Hampshire Democratic primary.

The big picture: Warren "entered February with among the least money in the bank, only $2.3 million, of any candidate" the New York Times reported two days ago.

U.S. Supreme Court Justice Sonia Sotomayor issued a dissenting opinion on Friday against the court's 5-4 vote to allow the Trump administration to penalize immigrants likely to rely on public programs like food stamps and Medicaid.

The big picture: The Trump administration has consistently tried to get controversial cases in front of the Supreme Court as quickly as possible, routinely asking the high court to step in before appeals courts have a chance to rule, Axios' Sam Baker reports. Sotomayor is apparently expressing her dissent at this new arrangement as well as the ruling itself.

Center-left think tank Third Way urgently called on the Democratic front-runners of the 2020 presidential election to challenge Sen. Bernie Sanders on the South Carolina debate stage on Feb. 25, in a memo provided to Axios' Mike Allen on Saturday.

What they're saying: "At the Las Vegas debate ... you declined to really challenge Senator Sanders. If you repeat this strategy at the South Carolina debate this week, you could hand the nomination to Sanders, likely dooming the Democratic Party — and the nation — to Trump and sweeping down-ballot Republican victories in November."

Catch up on today's biggest news:

1. Warren campaign says it raised $14 million since New Hampshire
2. Justice Sotomayor: Rushing Trump admin's legal challenges "comes at a cost"
3. CNN's Cooper scolds Blagojevich in heated exchange over criminal justice reform
4. Warren Buffett releases annual letter, reassures investors about future of Berkshire Hathaway
5. Centrist Democrats beseech 2020 candidates: "Stand up to Bernie" or Trump wins

Greyhound said it will stop allowing Border Patrol agents without a warrant to board its buses to conduct routine immigration checks, AP reports.

What they're saying: The company said it'll notify the Department of Homeland Security that it does not consent to unwarranted searches on its buses or in areas of terminals that are not open to the public.

Today's Nevada caucus will foreshadow the future of American politics well beyond 2020.

Why it matters: The U.S. is in the midst of a demographic transformation, and the country's future looks a lot like Nevada's present. Today's results, in addition to shaping the 2020 race, will help tell us where politics is headed in a rapidly changing country.

Twitter has reportedly suspended about 70 accounts posting pro-Bloomberg content, the Los Angeles Times reports.

The big picture: The presidential campaign is paying Instagram, Facebook and Twitter users in California to post messages of support on their personal accounts, the Wall Street Journal reported this week. That effort could "later be deployed nationwide," per WSJ.

Retired Navy Admiral William McRaven, who oversaw the 2011 Navy SEAL raid that killed al-Qaeda leader Osama bin Laden, defended former acting Director of National Intelligence Joseph Maguire in a Washington Post op-ed on Friday.

What he's saying: "...in this administration, good men and women don’t last long. Joe was dismissed for doing his job: overseeing the dissemination of intelligence to elected officials who needed that information to do their job," McRaven writes.

Election volunteers in charge of tallying results in Saturday's Democratic caucus are being asked to sign legal agreements to keep them from hurting the reputation of the Nevada Democratic Party, the Washington Post reports.

Why it matters: These nondisparagement agreements come after Democrats used an app created by Shadow Inc. that threw Iowa's caucuses into disarray, leading to delayed results amid evidence of an error-riddled process.