National Republicans have not embraced the independent Senate bid of former Maine Gov. Angus King, arguing that he is a stealth candidate for Democrats. But King said something over the weekend that might worry Democrats: He would caucus with the GOP if it is more advantageous for his state.

"I have not made up my mind whatsoever," King told a local television station (video below).

"A lot will depend on what the numbers are, and depend upon what the actual circumstances are," King said. "My judgment is going to be based on what's going to make me most effective on behalf of Maine. If I can get away with not caucusing with either side, that's my preference. If the numbers work out in such a way that it will be beneficial to Maine, that's the basis upon which I'm going to make this decision."

Even before King stated his standards for allegiance in the Senate, he had already attracted criticism from a Democratic competitor, state Sen. Cynthia Dill, who told Politico, "It's quite frightening to hear Gov. King may or may not caucus with Democrats."

If King wins and his inclination is to side with Democrats, Republicans would have to net five seats in other contests to take control of the Senate and make it worth King's while to side with them. Should the Senate wind up deadlocked 50-50 (with King as a Democrat), the Republicans could conceivably woo him over to their side of the aisle with a compelling offer.

Republicans would very much like to raise doubts about King among Democrats in the state, hoping that a split between Democrats and independents would clear the way for a GOP nominee to beat the popular former governor. They've already tried to raise doubts about King generally with a scathing online video that accuses King of cutting a secret deal with Democrats. King adamantly denies that charge in the interview below.

The National Republican Senatorial Committee tried to stoke fears with a press release Monday afternoon.

"If national Democrats truly believe that Maine represents 'a top pick-up opportunity' for their party, many are rightfully asking the same question that Cynthia Dill and other Democrats are no doubt wondering with the filing deadline just days away -- where's the cavalry?" NRSC spokesman Brian Walsh said. "The decision by national Democrats to give the cold shoulder to yet another announced female Senate candidate not only undermines their 'year of the woman' talking point, but it also makes clear their belief that they already have Angus King's vote in Harry Reid's pocket."