ODESSA, TX – Mitt Romney returned to Texas oil country Tuesday to fuel his campaign coffers with nearly $7 million raised in just one day, largely with money from top energy industry executives.

So far this presidential campaign, Romney has extracted $13.9 million dollars in contributions from Texas, making it the second best fundraising state for the GOP nominee after cash-cow California. New York, with its massive financial sector, comes in a close third.

Unlike previous fundraising swings through the nation's largest oil-producing state, which have netted millions for Romney's campaign and the GOP Victory fund, Romney's two-step through Houston and Midland this time is geared at the oil and gas industry, and comes as the candidate is preparing to further outline his energy policy at a campaign event in New Mexico later this week.

Romney started his day with a luncheon at the Houstonian Hotel that was hosted by energy industry titans including Rex Tillerson, CEO of oil and gas giant Exxon Mobil, and L.E. Simmons, a fellow member of the LDS church and Romney's Texas finance chairman, who made his millions investing in the booming energy sector here. 

Harold Hamm, a billionaire pioneer in modern drilling techniques who spearheaded oil and gas development in North Dakota, now America's second largest oil producing state, was also in attendance at the $50,000 per person event, where Romney relayed his story as an example of bold economic risk taking.

Romney told this audience he planned to roll out more detail on his energy policy but said he would offer them a first look behind closed doors. 

"I know that we have members of the media here right now, so I'm not going to go through that in great detail so I can save a bit of that until a little later in the week. But your input is something I wanted to retain before we actually cross the ‘t’s and dot the ‘i’s on those policies," Romney said, telling some 125 top donors that his energy plan, centered on fossil fuels like oil, gas, and coal would do a better job taking advantage of America's natural resources than that of President Barack Obama, echoing a common stump speech theme.

The presumptive GOP nominee has long focused on developing America's natural resources, particularly oil, gas, and coal as a key to unlocking the stagnant economy. He lists it first on his five-point plan to restore the economy at nearly every campaign event, and just last week accused Obama of waging a "war on coal," which he claims stifles job creation, particularly in coal-rich (and electoral-vote-rich) Ohio and Pennsylvania. 

Romney has come out against extending tax breaks for wind energy development, joking that you can't put a windmill on your car, and arguing for the economic necessity of expanding fossil fuel development in the near term.

Democrats have subsequently accused Romney of being in the pocket of oil companies, and of ignoring alternative energy, questioning how his energy plan, which thus far lacks specifics beyond a pledge to reach North American energy independence by 2021, is any different from the much-derided "Drill baby, drill" mantra of Republican candidates in 2008.

The final stop on Romney's energy pilgrimage comes Tuesday night at the Petroleum Club of Midland, where an invitation obtained by NBC News listed exploration and drilling company Concho Resources executives Timothy Leach and Jack Harper as event hosts, alongside Statewide Minerals owner Miles Boldrick, whose company website claims over 25,000 oil and gas wells nationwide.

For Romney, while the details of his energy policy remain to be seen, the cash well still runs deep.