“Aggregate limits” seem technical, but the issue is simple. Invalidating aggregate limits would allow an elected official to ask a wealthy contributor for a single check of about $3 million, which would open the door to quid pro quo corruption.
In 2012, for example, the Obama campaign solicited checks as large as $75,800 for the Obama Victory Fund (a joint fundraising committee)—with $30,800 going toward the DNC, $40,000 to Democratic state parties, and $5000 going toward the Obama campaign. Mitt Romney did the same. Significantly larger checks were not solicited only because of the aggregate limits. These victory funds are not outliers—in 2012 they were the mainstay of presidential major donor fundraising and tied to pretty much all fundraising events once it was likely the candidate would be the party’s nominee.
If the Court strikes the aggregate limits, a federal elected official (President, Senator, Congressperson) would be able to ask a wealthy individual for a $3 million check, which would be divided between the elected official’s national and state party committees, and as well as fellow party members running for all U.S. House and Senate seats nationwide. As evidenced during the Watergate and soft-money era scandals (which led to reforms), solicitation by elected officials of these large contributions will result in more explicit quid pro quo corruption.