Former Gov. Tim Kaine’s Senate campaign purchased another $1 million in television airtime for the fall.

The addition brings the Democrat’s total spending for airtime in the campaign’s final months to $3.5 million. Politico first reported the move Monday.

The campaign of Kaine’s Republican opponent, George Allen, has reserved about $3 million of post-Labor Day TV airtime, according to a source close to the campaign. That figure is expected to jump to $3.4 million by the end of this week.

The blockbuster Senate race between the two former governors — Allen is also a former Senator — is likely to be one of the closest in the country, and Roll Call rates it as a Tossup.