After going up with its first independent-expenditure ad in Pennsylvania this week, the National Republican Senatorial Committee is expanding its investment in the hopes of sealing the deal for its candidate, Pat Toomey, who leads Democratic Congressman Joe Sestak by single digits in the state's Senate race, according to major polls.

From Hotline OnCall's Jeremy Jacobs:

The NRSC had originally planned to spend $1.7M statewide on air time. It is now planning $3.4M, according to committee sources. That's the same amount that the DSCC is planning to spend on air time in the next two weeks.

Read the full story at Hotline OnCall.

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