Although Rice got less than 60 percent of the vote in defeating a perennial candidate in the primary, he said his campaign got a lift, according to internal polling and polling by the Democratic Senatorial Campaign Committee, after he spent $307,000 on television advertising.

He plans to begin running more ads after Labor Day, while he says Inhofe has bought air time through to the Nov. 4 general election.

"We will be going up and be competitive from week to week as we build on our campaign funds," Rice said.

Bob Darcy, an Oklahoma State University political professor, said it will be difficult for Rice to overtake Inhofe.

"He's running a vigorous campaign, but he is not going to be helped at the top of the ticket, not at all," Darcy said of the likelihood of a poor showing by Democrat Barack Obama in the presidential race in Oklahoma.

On the other hand, Darcy said Rice is the type of candidate who can pull off a surprise, a legislator with not much of a record to target.

"That is the kind of guy we elect senator," he said.

Little-known legislators who won statewide races include Democrat David Boren, who was elected governor in 1974, and Republican Don Nickles, who became a U.S. senator in 1980.

One of Rice's ads said Inhofe has been in Washington 22 years and has "lost his way." Another commercial highlights his efforts to pass legislation to expand health care coverage.

Examples of "losing his way," Rice said, were Inhofe's votes against delaying Medicare cuts and student loan spending.

He said he was surprised Inhofe had run commercials touting his leadership on the cleanup of the Tar Creek Superfund Site after initially opposing a buyout for homeowners in the area.

He said while Inhofe takes credit for protecting state military installations and bringing military contracts, that is "basic stuff" that any other senator would do.

"Not fighting for Tinker and Fort Sill, I think is sort of akin to David Boren announcing this next week that he is going to cut the football budget by 50 percent," Rice said.

Josh Kivett, the campaign manager for Inhofe, said the incumbent's campaign is confident Oklahoma voters "will once again cast their vote for Sen. Inhofe and his record of leadership for our state."

Kivett called Rice's criticism "almost laughable" and added: "It seems Sen. Rice will say whatever it takes to get elected.”