Story highlights "She's not doing any big money fundraisers any more," a Clinton ally says

She hopes donors work on behalf of a Democratic Senate majority

(CNN) Hillary Clinton's campaign has a message to its big donors: Send your money down-ticket to win back a Democratic Senate majority.

That's the implicit signal being sent by Clinton's allies to their big donors in the final two weeks of the campaign season. A Clinton ally tells CNN that the Democratic nominee has no more campaign fundraising events, and instead wants her maxed-out donors to try to win back a Senate majority.

"At this point, she's not doing any big money fundraisers any more because she wants people to be giving to Senate campaigns," a Clinton ally says.

Specifically, Clinton allies wants its top bundlers and deep-pocketed donors to give money to Senate Minority Leader Harry Reid's super PAC, the Senate Majority PAC. Already Clinton donors have given a combined $7.5 million to the super PAC, the source says, with more to come in the coming days.

While candidates don't often raise money in the final two weeks of the campaign, Clinton's move underscores just how close the battle is for control of the Senate. Democrats need to pick up four seats if Clinton wins the White House, and they have ample opportunities in seven states controlled by Republicans, defending just one in Nevada.

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