Posted Wednesday, September 12, 2012 --- 7:40 a.m.

MADISON, Wis. (AP) -- President Barack Obama plans to begin airing television advertisements in Wisconsin starting on Wednesday, another sign of the state's increasing importance in the race.

The ads are the first in Wisconsin from Obama's campaign and they come after Republican Mitt Romney started running his own spots on Sunday.

Obama for America spokeswoman Gillian Morris said Tuesday the campaign will not provide details about the scope or size of the buy. She says the ad would not be made public until Wednesday.

The announcement comes as both Obama and Romney's campaigns are placing greater emphasis on Wisconsin and its 10 electoral votes. Romney running mate Paul Ryan planned to be in Green Bay on Wednesday and Vice President Joe Biden was to be in Eau Claire on Thursday.

Copyright 2012. The Associated Press.