Paul Ryan, Dana Rohrabacher, and Mark Meadows. Photos: AP

American Action Network, a center-right issue advocacy organization focused on tax reform, is launching a $500,000 digital ad arguing the Trump administration's tax plan will result in $1,200 tax cuts for middle class families.

Why it matters: The ad targets 42 Congressional districts represented by Republicans from leadership, key committees, Freedom Caucus, and those in vulnerable seats whose support on tax reform is critical.

The group's Middle Class Growth Initiative is behind the ad, which will run on platforms like Facebook, YouTube and Twitter for two weeks in the targeted districts. The middle-class tax cuts highlighted by the ad are based on an independent analysis featured on Forbes.

Some of the key Republicans targeted: House Speaker Paul Ryan, Freedom Caucus Chair Mark Meadows and Rep. Dana Rohrabacher. Watch the ad.

Go deeper: Republicans agreed to raise the bottom rate and double the standard deduction.

Go deeper

41 mins ago - Health

More Republicans say they're wearing masks

Data: Axios/Ipsos poll; Chart: Andrew Witherspoon/Axios

Nearly two-thirds of Americans — and a noticeably increasing number of Republicans — say they’re wearing a face mask whenever they leave the house, according to the latest installment of the Axios-Ipsos Coronavirus Index.

Why it matters: A weakening partisan divide over masks, and a broad-based increase in the number of people wearing them, would be a welcome development as most of the country tries to beat back a rapidly growing outbreak.

Buildings are getting tested for coronavirus, too

Illustration: Eniola Odetunde/Axios

Testing buildings — not just people — could be an important way to stop the spread of the coronavirus.

Why it matters: People won't feel safe returning to schools, offices, bars and restaurants unless they can be assured they won't be infected by coronavirus particles lingering in the air — or being pumped through the buildings' air ducts. One day, even office furniture lined with plants could be used to clean air in cubicles.

56 mins ago - Science

The summer of Mars

Illustration: Aïda Amer/Axios

Three missions from three different nations are heading to Mars in the next month — including one from the United Arab Emirates, a newer player in planetary exploration that is expected to launch its first spacecraft to the Red Planet this evening.

Why it matters: More nations are now going to space as the costs of launch and development are driven down. Mars is a step farther that is reserved for those with the most ability and resources — missions to the planet are a mark of scientific and technical prowess on the global stage.