Polls show Democrats have a good chance of capturing the Senate majority in November, but a growing number of Democratic senators are concerned Russian interference could lead to a different outcome on Election Day.

Senate Democrats say Russian operatives are already waging a disinformation campaign aimed at disrupting the 2020 election, and at least one senator says bots with suspected ties are waging Twitter attacks on their campaign.

The lawmaker, who is in a competitive race, has asked social media companies to help quash the effort.

Democratic senators also say that Russian disinformation is also being used to fuel a Senate GOP investigation into Democratic presidential nominee Joe Biden and his son Hunter — a charge vigorously denied by the GOP senator leading the probe.

Sen. Ron Wyden (D-Ore.), a member of the Senate Intelligence Committee, said Russian interference is in full swing.

“This is going on right now, according to the nation’s intelligence leadership,” he said. “You’ve got the intelligence leadership saying the Russians are working very hard to do in 2020 what they tried to do in 2016. That’s the biggest tell out there.”

Wyden declined to provide details, citing the classified nature of the subject matter.

“I’m constrained by a fair measure because I’m on the committee,” he said, referring to his access to classified information as a member of the Intelligence Committee. 

William Evanina, the director of the U.S. National Counterintelligence and Security Center, issued a statement last month saying Russia “is using a range of measures to primarily denigrate former Vice President Biden and what it sees as an anti-Russia ‘establishment.’”

Democrats are now sounding the alarm in hopes of avoiding a repeat of 2016. 

Four years ago, former President Obama and senior members of his administration were aware in the fall of 2016 of attempts by Russian intelligence agents to influence the results of that year’s presidential election but declined to go public, worried that their  warnings would be seen as attempts to politicize intelligence or interfere in the election.

One of the few Democrats to speak out four years ago was then-Senate Minority Leader Harry Reid (D-Nev.), who asked now-former FBI Director James Comey to investigate evidence that Moscow was trying to alter the outcome of the election. 

Reid warned that the Kremlin’s efforts to manipulate the election were “more extensive than is widely known and may include the intent to falsify official election results.”

Obama told Russian President Vladimir Putin directly at a Group of 20 meeting in China in September 2016 “to cut it out” and warned “there were going to be serious consequences if he did not.” The warning had no effect.

But Obama decided not to speak out publicly on the threat posed by the Kremlin during the height of the 2016 campaign after Senate Majority Leader Mitch McConnell (R-Ky.) declined to sign a bipartisan statement condemning Russia.

Wyden says Democrats didn’t act forcefully enough or quickly enough back then.

“I think more should have been done early,” he said.

Wyden said senior U.S. intelligence officials need to do more before Election Day to warn the public about ongoing Russian interference.

“I want them to put out more information, more specifics and not do what they did in 2016 which is be kind of cautious,” he said. 

Sen. Chris Van Hollen (D-Md.), who served as chairman of the Democratic Senatorial Campaign Committee during the 2018 election cycle, said he’s “very concerned” about Russian interference in both the presidential and Senate races.

“The intelligence community has said that interference is ongoing,” he said.

He said Senate Democrats plan to force another Senate vote on the DETER Act, which would require the director of national intelligence (DNI) to issue to Congress a finding within 60 days of the election whether any foreign government has interfered with that election.

If the DNI concludes that Moscow again interfered with the election, sanctions on major sectors of the Russian economy, including finance, energy and defense, would be required within 30 days.

Van Hollen said Russia is trying to interfere by using many of the same tactics employed during the 2016 election, such as hacking into Democratic computers in order to leak sensitive information and posting disinformation on social media through agents or bots posing as Americans.

“This time the good news is the social media companies, while not perfect, are taking much stronger action,” he said. “Four years ago, we did not have our defenses up.”

Twitter and Facebook announced earlier this month that they had closed a network of accounts linked to Russia’s Internet Research Agency after working with the FBI’s foreign influence task force. 

FBI Director Christopher Wray on Thursday told members of the House Homeland Security Committee that U.S. intelligence officials “have seen very active efforts by the Russians to influence our election in 2020.”

He cited Russian activity through “social media, use of proxies, state media, online journals.”

The Democratic senator who described coming under attack by bots suspected of Russian links, told The Hill: “We have seen evidence of bots that are operating to respond to tweets that don’t represent real people.”

“They’re going after me,” said the lawmaker, who requested anonymity to discuss a sensitive campaign subject. “So we’ve been working with a number of entities to try to shut that down to the extent that we can.”

Sen. Gary Peters (D-Mich.), who is also in the midst of a competitive race, said “we have to be very vigilant” about Russian interference in Senate races.

He said he didn’t have “direct knowledge” of Russian attempts to influence his reelection bid but cautioned “sometimes it’s difficult to discern.”

Democrats say social media and hacking aren’t the only ways to interfere in an election.

Senate Democrats have accused Senate Homeland Security Committee Chairman Ron Johnson (R-Wis.) of using Russian-spread disinformation in his panel’s investigation of whether Joe Biden used his influence as vice president to help his son Hunter’s business dealings in Ukraine — a discredited theory promulgated by President Trump’s personal lawyer Rudy Giuliani.

Senate Democratic Leader Charles Schumer (N.Y.), Wyden and Peters introduced a resolution Wednesday calling for a cessation of any Senate investigation or activity that allows Congress to act as a conduit for Russian information, a move directed squarely at Johnson.

Wyden noted on the floor Wednesday that Andriy Derkach, who has been identified as an active agent for Russian intelligence, met with Giuliani.

Evanina, the director of the counterintelligence and security center, in his August statement singled out Derkach, a pro-Russia Ukrainian parliamentarian, as spreading claims about corruption “to undermine Vice President Biden’s candidacy and the Democratic Party.”

Wyden said on the floor that Derkach’s “disinformation became the basis of much of the work” of Johnson’s inquiry, prompting an angry denial from the Wisconsin Republican.

“We did not solicit; we did not accept; we did not receive any information from Mr. Derkach whatsoever. Yet Democrats persist in pushing this false allegation,” Johnson insisted during an angry floor colloquy with Wyden.