This month's political party conventions will cost tens of millions of dollars, and it's not just rich donors covering the bills.

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U.S. taxpayers will spend at least $100 million.

Congress allocated $50 million to state and local law enforcement in Ohio for security measures at the Republican National Convention in Cleveland.

Authorities in Philadelphia, the site of the Democratic convention, will also get $50 million for security.

Other costs to taxpayers include the undisclosed amount of money that the Secret Service will spend to protect the nominees and their families at the conventions and to accompany President Obama when he travels to attend his party's convention.

Organizers at both conventions will not receive any public funds directly for the first time since 1976.

Congress voted to end the Presidential Election Campaign Fund, which allowed taxpayers to contribute $3 toward the conventions.

In 2012, both party conventions each received $18.2 million using the fund for a total of $36.5 million.