Former U.S. special envoy to Ukraine Kurt Volker testified in an impeachment hearing Tuesday that allegations against Joe Biden and former Ambassador to Ukraine Marie Yovanovitch, which were promoted by former Ukrainian Prosecutor General Yuriy Lutsenko and spread in the U.S. by Rudy Giuliani, are "self-serving and not credible."

Why it matters: These allegations are now at the heart of the impeachment inquiry, as President Trump and Rudy Giuliani have come under scrutiny for working to push Ukraine to investigate Biden for corruption. Volker, who is one of the witnesses called by Republicans, is one of multiple officials who have testified that the allegations against Biden and Yovanovitch are baseless.

Go deeper: Live updates from Volker and Tim Morrison's testimony

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An election like no other

Illustration: Eniola Odetunde/Axios

The coronavirus will make the 2020 presidential election different from any in modern history: Voting that begins earlier, results that take longer, mail carriers as virtual poll workers and October Surprises that pop in September.

The big picture: Perhaps 80 million Americans will vote early, by mail or in person, Tom Bonier, CEO of TargetSmart, a Democratic political data firm, tells Axios. That's going to set up more of an Election Season than an Election Day — and increase the odds of national turmoil over the vote count.

Exclusive: Inside McCarthy's new GOP messaging platform

House GOP Leader Kevin McCarthy (R-Calif.). Photo: Tasos Katopodis/Getty Images

House Republican Leader Kevin McCarthy (R-Calif.) has given his GOP colleagues new marching orders for stump speeches between now and November, as incumbents worry about how President Trump's own challenges may strain their re-election bids.

Driving the news: McCarthy delivered a PowerPoint presentation to the GOP conference in person last Thursday at the Capitol Visitor Center, with several members joining via Zoom, lawmakers and aides familiar with the gathering tell Axios.

Biden launches $280 million ad push

Photo: Mark Makela/Getty Images

Joe Biden's campaign is launching a $280 million TV and digital ad campaign heading into the fall, targeting 15 states with a message — delivered directly from Biden — about the coronavirus pandemic and the economy.

Why it matters: The size of the buy, which advisers described on a call with reporters Tuesday night, signals a campaign that isn't worried about burning through cash — and it may force the Trump campaign, or associated super PACs, to increase their spending in response.