Senate Republicans blocked a bill today that would provide $2.7 billion in funding to address the crisis of minors from Central America illegally entering the U.S.

With 50 yeas and 44 nays, the Senate did not advance Sen. Barbara Mikulski's, D-Md., proposal to provide funding in response to President Obama's request. The measure required a 60-vote threshold.

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On July 8, the president asked Congress to supply an emergency $3.7 billion to address what members of both parties have deemed a national crisis. That request included $1.1 billion to improve enforcement and detain and return adults accompanying children across the border, plus about $2.2 billion to help Customs and Border Patrol and the Department of Health and Human Services detain, house and care for children after they have crossed.

In response to that request, Mikulski proposed a pared-down $2.7 billion package.

Under Senate rules, all non-emergency funding must include spending offsets, and 44 Republicans voted against waiving those rules and proceeding to a vote on Mikulski's spending package. All 50 Senate Democrats voted to waive budget rules and proceed to vote on the bill.

House Republicans struggled today to corral members for a vote Friday on their own border bill, but the Senate bill's failure ensures that Congress will not send a border measure - much less the $3.7 billion in funding he requested - to President Obama's desk before its August recess.

The House will convene for a border vote Friday before leaving town for August recess. After voting late into the night today, the Senate will be in session without holding any votes on Friday, its last day before the month-long break.