Washington (CNN) – While Mitt Romney’s major challengers suspended their campaigns and the primary season essentially ended in April, donations to the super PAC supporting Romney's candidacy and its spending slowed down as well, according to a monthly financial report filed Sunday with the Federal Election Commission.
Restore Our Future brought in $4,608,000 in donations in April and spent $2,852,000, compared to March when the PAC received $8,680,000 in donations and spent $12,722,000.
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The group ended April with $8,210,000 cash on hand, which is more than the $1.5 million it had at the beginning of the month.
Bob Perry, a Houston, Texas homebuilder and donor to major Republican groups was one of the notable contributors. He gave $750,000 to Restore Our Future in April bringing his total donations to the group to $3.75 million. Harold Hamm, an energy adviser to Romney, gave his first donation of $985,000 to Restore Our Future last month. Hamm is listed by Forbes as the 30th richest person in the United States and is CEO of Continental Resources. Investment manager John Kleinheinz also donated for the first time. He gave $1 million to the PAC.
One notable person still not on the list was Nevada casino owner and billionaire Sheldon Adelson. Adelson and his family contributed more than $20 million to Winning Our Future, the super PAC backing Newt Gingrich and almost single handedly kept the group alive before Gingrich suspended his campaign. As CNN previously reported, Adelson indicated he would support the eventual Republican nominee. Some financial supporters of Romney met with him in March to urge him to financially back the former Massachusetts governor.
Last month Adelson told Las Vegas Sun political columnist Jon Ralston he wanted to become less visible in the political world and that references to him being a mogul at the time of his donations were “not helpful to that person.”
When asked if he was going to give to the Republican super PAC American Crossroads or its non-profit affiliate Crossroads GPS, he initially would not answer. Later, he told Ralston "I'm going to give one more small donation - you might not think it's that small - to a super PAC and then if I give it will be to a C4," referring to 501(c)(4) non-profit groups, such as Crossroads GPS, which are not required to disclose their donors. Adelson refused to say if his “small” donation reference was to Restore Our Future.
"I'm not going to tell you ... you'll find out when it's reported," he said.