Why it matters: The past election cycle showed just how much modern campaigns lean on programmatic advertising to reach voters and donors with persuasive ads that could push them to vote one way or another.

The back story: Per Borrell Associates, $800 million was spent on automated advertising on Google and Facebook during last year's election. The Trump campaign spent nearly as much money on programmatic ads as they did on TV ads.

Where it gets tricky: It will be hard for the six-person commission, divided equally among party lines, to come to a consensus around this, according to sources within the FEC, meaning that any major disclosure efforts would have to come from Congress.

• Republican commissioners have traditionally approached regulations around election disclosures with hostility, and in order to push measures forward, two of the three Republican commissioners would need to break with party lines, because a Democratic commissioner seat is vacant at the moment.

Timing: The commission is accepting comments for 30 days. After that, FEC Commissioner Ellen Weintraub tells Axios, "I think things are moving fast and we need to get moving fast."

Focus on the Hill: The commissioners are also keeping an eye on an idea being floated by Sens. Amy Klobuchar and Mark Warner on Capitol Hill to build out some sort of database of political ads. The big questions around who would keep it, maintain it, and be able to access it are still being worked through. But at this point, any actual mandates would need to come from Congress, not the FEC.

Focus on the Valley: "These are issues that the commission needs to hear from people in tech community," says Weintraub. "I'm hoping we'll hear from Facebook, Google, Twitter and the rest of the tech community who have a lot of expertise to share."

"It is the technology companies that have the resources and knowledge to make meaningful disclosure a reality. They should be leading the way," says Jason Rosenbaum, the director of advertising for Hillary Clinton's presidential campaign and former Google ad sales director.

The database push: Based on comments to the FEC and lawmakers' statements, the most likely consensus would be to require publishing platforms like Facebook, Google, or Twitter to turn over all their metadata to the commission, which would keep it and make it searchable through the FEC's website.

The FEC would require platforms to keep ads on their sites for a certain amount of time and would link back to those ads from a searchable FEC database. Congress would need to pass a law to make publishing platforms comply.

Speed bump: Several sophisticated political ad buyers tell Axios that they don't believe Facebook doesn't has the technology yet to house all of those ads on a single page, something Mark Zuckerberg announced the platform would require last week. (The Trump campaign, for example, tested 40-50,000 different ads every day during the election.)

Others worry that laws that aren't carefully thought through could make things worse.

"Targeted free speech is no different than megaphone free speech," says Gary Coby, who managed advertising for the Trump campaign. "If and when foreign governments aim to influence our elections, they must be stopped. But, Congress, Facebook, and the FEC, should be careful to avoid unintended consequences that end up censoring free speech and hampering the democratic process."

Who’s on board: Sens. Ron Johnson, Lindsey Graham and Rand Paul — so far.

Be smart: Writing budget resolutions and reconciliation instructions is complicated, but here's all you need to know: It would be possible to do both tax reform and health care through the same budget vehicle. So the argument isn't about whether this is possible — it's about whether the GOP should do it.

Johnson and Graham might be able to force the party's hand. "If we're not able to pass this this week, both Lindsey Graham and I have said — we're both on the Budget Committee — we'll insist on a budget resolution that'll give us the tools of reconciliation for health care and for tax reform," Johnson told reporters Monday.

• Paul told reporters on Monday that "there's no reason you couldn't do health care and taxes at the same time."
• Like health care, passing a budget — and then tax reform later — will only require 50 votes. However, that means Republicans can only lose two votes on a partisan bill to still pass it, with Vice President Mike Pence's tie-breaking vote.
• "This will be the next problem [because] they won't have 51 votes for the budget," a GOP lobbyist said, adding that as far as tax reform goes, "I think this whole thing is going to get derailed by health care."