Largely ignored by the mainstream media for most of the presidential campaign, Libertarian Party nominee Gary Johnson is suddenly racking up headlines in The Washington Post and New York Times and on CNN and NPR.

Volume of coverage is a difficult thing to quantify comprehensively, but consider one striking metric: Lexis-Nexis, which logs articles and transcripts from thousands of news outlets, tallied 452 stories related to Johnson in U.S. media between May 18, the day he tapped former Massachusetts Gov. Bill Weld as his running mate, and June 3. That’s more attention in a 17-day span than he had received in 4½ months of campaigning to that point.

Several factors likely contributed to the spike in interest. Adding Weld made a decent-size splash. A former Republican governor of a politically important state is certainly a bigger newsmaker than, say, a former county judge, which is what Johnson had on the Libertarian ticket in 2012.