A Bloomberg Businessweek article about a meeting of Republican donors explains how the reporter got into the meeting:
I was invited as the guest of a financier who is a significant Republican donor. The financier knew that I was a journalist. At no point was I presented with, nor did I agree to, restrictions regarding the information I heard. Upon my arrival at the breakfast, I was not asked if I was a journalist. I gave my name, identified the person who had invited me, was handed a wristband, and ushered into the dining room. American Crossroads disputes this version of events, but a spokesman did not immediately return calls to elaborate.
The "financier" did the Bloomberg reporter a favor. The transparent move would be to identify the financier so readers who see the person mentioned in future articles by this reporter or news organization can assess for themselves if the favor is being repaid.