The Democratic Senatorial Campaign Committee is not airing ads for Alison Lundergan Grimes the last three weeks of her challenge to incumbent Republican Mitch McConnell, Roll Call reports.

Grimes has been under fire of late for refusing to say whether she voted for Barack Obama in the past two presidential elections. But Larry Sabato, director of the University of Virginia's Center for Politics, said that isn't the reason national Democrats are dropping Grimes.

"I think it's because she's unlikely to win," Sabato said Tuesday on Fox News Channel's "Your World with Neil Cavuto."

"They are transferring the money, in essence, to Georgia, where they actually have a better chance of at least forcing the Senate race into a Jan. 6 runoff."

Democrats had hoped to knock off the powerful McConnell, who is poised to become majority leader if re-elected and if Republicans win a majority of Senate seats, as most analysts, including Sabato, expect.

"The DSCC has now spent more than $2 million in Kentucky and continues to make targeted investments in the ground game while monitoring the race for future investments, but is currently not on the air in the state," a official with the DSCC told Roll Call.

With a Grimes victory looking increasingly unlikely, Democrats are now focusing their efforts on Georgia, where Michelle Nunn, daughter of former Democratic Sen. Sam Nunn, is taking on Republican David Perdue for the Senate seat being vacated by Republican Saxby Chambliss. Libertarian Party candidate Amanda Swafford is expected to force a runoff.

Sabato said Grimes was "too clever by half" in her insistence that her vote should remain secret to protect ballot privacy.

The issue has gotten legs, Sabato said, because Grimes refused to state the obvious.

"Everybody knows she voted for Obama. She should simply have said in the beginning, I'm an elected Democratic official. I voted Democratic as I usually do. It's my obligation to my party. That's it. You take the hit and you move on," he said.

Grimes, and most other Democrats running this year, have distanced themselves from Obama. But Grimes has to watch here step, Sabato said, because she needs strong turnout of the state's Democratic base, including minority voters, "to have any reasonable chance of even coming close."

Despite polls showing McConnell leading Grimes by only 4 percentage points, Sabato said his Crystal Ball website has always listed the Kentucky race as "likely Republican."

The Rothenberg Political Report/Roll Call lists Kentucky as "leans Republican."

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