I meant to link to this earlier, but better late than never: In response to some of the questions we raised Monday about the ways Romney's fundraising ability could benefit McCain, The Weekly Standard's Jaime Sneider had a conversation with former FEC commissioner and former Romney adviser Brad Smith. Here's what Sneider took away from it:
[Smith] tells me any money McCain raises can be spent on advertising and expenses incurred before the time he becomes the official nominee. That only happens at the Republican convention in September, so if Romney raises $60 million in the mean time, television airwaves will be flush with McCain ads all summer long. As an aside, friends on the McCain campaign tell me Romney is already busting his butt bundling checks.
With respect to Romney giving money, Smith says, he'll be capped at $50,000 under the campaign finance laws once he is the vice presidential nominee. And before that time, he's capped like everyone else, but can make unlimited independent expenditures.
I still think the financial upside is overstated--both because raising $50-$60 million would be extremely ambitious for one month (at least the old-fashioned way), and because Romney is already working so hard for McCain. But it's obviously not a trivial consideration.
Also, it's interesting that making Romney the veep nominee makes it harder to tap his fortune.