'Start Here': Biden holds lead with Warren, Buttigieg on the rise in new poll and whistleblower offers to answer GOP questions

Here's what you need to know to start your day.

It's Monday, Nov. 4, 2019. Let's start here.

1. 2020 roundup

Also topping the poll are Sen. Elizabeth Warren, D-Mass., at 23% and Sen. Bernie Sanders, I-Vermont, at 17%, with South Bend, Indiana Mayor Pete Buttigieg displacing Sen. Kamala Harris, D-Calif, in fourth place with 9%.

"Kamala Harris is in a really tough spot with her campaign," ABC News Political Director Rick Klein tells "Start Here" today. "They're looking for a new moment and she has basically shuttered all of her operations outside of Iowa... and it means an effort to try to get something sustained in a state that kicks things off."

2. Whistleblower offer

"The whistleblower gave a very inaccurate report about my phone call," Trump told reporters on Sunday. "My phone call was perfecto.”

ABC News has learned that the whistleblower is now offering to answer questions from Republicans on the House Intelligence Committee in writing and under oath, according to ABC News' Kyra Phillips on "Start Here."

3. TikTok concerns

Short-video app TikTok is reportedly under national security review over data privacy concerns surrounding its ties to China.

"TikTok is powered by these really powerful algorithms so it keeps feeding you more things you like... and that's an incredibly powerful engine for targeted advertising... [but] that's a lot of information for a country that's really not on good terms with the U.S. to have," Louise Matsakis, who covers e-commerce for Wired, explains to the podcast.

TikTok in a statement said, "We store all TikTok US user data in the United States, with backup redundancy in Singapore. Our data centers are located entirely outside of China, and none of our data is subject to Chinese law... We are not influenced by any foreign government, including the Chinese government."

"Start Here," ABC News' flagship podcast, offers a straightforward look at the day's top stories in 20 minutes. Listen for free every weekday on Apple Podcasts, Google Podcasts, iHeartRadio, Spotify, Stitcher, TuneIn or the ABC News app. Follow @StartHereABC on Twitter, Facebook and Instagram for exclusive content and show updates.


'Careless act': Milwaukee police have arrested a suspect in a fatal hit-and-run crash that killed two young sisters and injured their cousin.

'At ease with death': At a church service on Sunday, former President Jimmy Carter reflected on dying and expressed his thoughts on what would truly make American great.

'Could be stuck there for years': A barge that has been stuck atop some rocks in Niagara Falls for more than 100 years has finally shifted as a result of severe weather.

'No more money': President Donald Trump tweeted Sunday morning his first comments about the wildfires blazing through California attacking Gov. Gavin Newsom saying he has done a "terrible job" of forest management.

From our friends at FiveThirtyEight:

'Why Beto O’Rourke’s campaign failed': Although his candidacy once had great promise, O’Rourke’s exit from the race came down to his weak poll numbers and reduced fundraising numbers, as well as the fact that he may never have had the base of support he needed to truly compete for the Democratic nomination.

Doff your cap:

Following their improbable run in the playoffs, and even more amazing World Series victory in which they won all four of their games on the road against the Houston Astros, the Washington Nationals capped off their championship celebrations Saturday with a World Series victory parade through the streets of D.C.

Following Saturday’s celebrations, the team will make the quick jaunt to the White House Monday for a ceremony hosted by President Donald Trump.