Mitt Romney began airing commercials Wednesday on national cable networks at a cost of some $2 million in an attempt to boost his standing among the leading Republicans seeking the presidency.

The campaign also renewed an ad campaign in Iowa and New Hampshire, a Romney adviser said. Most of the national ads will run on Fox News, a strategic effort by the campaign to reach conservative voters.

Republican presidential candidate Mitt Romney and his wife Ann, talk to reporters during a campaign stop at the Florida Capitol, Monday, April 23, 2007, in Tallahassee, Fla. (AP Photo/Phil Coale) (Phil Coale - AP)

The adviser spoke on the condition of anonymity because the campaign does not publicize its ad strategy. In the national ad, called, "I like Vetoes," Romney, the former governor of Massachusetts, says that as president he would demand that discretionary domestic spending be capped at 1 percent less than the rate of inflation.

"If Congress sends me a budget that exceeds that cap I will veto that budget," Romney says. "I like vetoing."

Besides Fox, the ad also will run on CNBC, MSNBC and CNN. The total cost of airing the ads is expected to be about $2 million and will run for more than a month.