Washington (CNN) - Mitt Romney travels to London Wednesday for a fundraiser and meetings, campaign aides said, becoming the first presidential candidate this cycle to campaign abroad. The former Massachusetts governor will hold an event at the prestigious Dartmouth House Wednesday evening before a meeting with a British official.

Romney, who experts say has the strongest donor network, brought in $18.25 million in total receipts for the 2nd Quarter, which ended June 30, according to his campaign. The money brought in at the London event will give him a head start toward what he hopes will be an impressive haul for the current quarter, which began July 1.