Story highlights The Senate now is in a 30-hour period of debate before holding a final vote this week

The Director of National Intelligence helped convince reluctant senators to back the bill

Washington (CNN) In a surprisingly close vote, the Senate advanced legislation Tuesday that would keep in place a key electronic surveillance tool the government says it needs to track terrorists, barely overcoming objections from a bipartisan group of civil libertarian-focused senators who wanted to add changes to the bill.

By a vote of 60-38, the Senate defeated a filibuster of the bill that reauthorizes Section 702 of the Foreign Intelligence Surveillance Act. Critics of the bill needed 40 votes to stop it from moving forward and came just two votes short.

The Senate now enters a 30-hour period of debate before holding a final vote later this week.

Section 702 allows the US government to collect communications, such as emails and phone records, of foreigners on foreign soil without a warrant. While the law targets non-US citizens, critics warn the government may incidentally monitor US citizens who are communicating with non-US citizens outside the United States.

While the vote stalled on the Senate floor for close to an hour and a half, undecided members were lobbied by opposing parties. Republican leaders also brought in Director of National Intelligence Dan Coats to persuade reluctant senators to vote yes.

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