MISSOULA, Mont. -

Senator Jon Tester announced the Postal Service will not close mail processing centers in Butte, Helena, Kalispell or Wolf Point during the state's primary election season.

Tester said it will help prevent problems with absentee voting, but said he'll keep working to make sure the post offices stay open permanently.

?When they start closing down these mail processing centers it's going to alter the ability for the Postal Service to deliver the mail on timely basis across the board. Whether it?s an election time, or the end of the month delivering birthday cards or whatever it may be,? said Tester.

There are nearly 635,000 registered voters in the state, 47% of them cast absentee ballots in 2010.