"Defeating Chris Christie in New Jersey would be a huge blow to his 2016 ambitions. We need you in this game now. All gifts are matched 2-to-1 today!" the email reads.
Christie has not yet indicated his 2016 plans, but he's widely considered to be a likely contender for the Republican nomination for president. He said this month he has no plans to decide about his political future until 2015.
But the tone of Buono's message makes it sound almost inevitable, possibly creating greater incentive to for donors to act than the upcoming November gubernatorial contest.
Buono substantially lags Christie in every poll of the race, and she has had trouble gaining attention and support up against the well-regarded governor.
The second-quarter fundraising deadline is this weekend, and the email is an attempt to boost her numbers in the final days before the books close.