Missing from Romney's latest campaign schedule were winner-take-all states of New York, New Jersey and Connecticut, which account for 180 of the 1,023 delegates at stake. The omissions were telling with voting in 21 GOP contests on Tuesday.
The former Massachusetts governor was in Colorado Friday and planned to attend the funeral of Mormon church President Gordon B. Hinckley on Saturday in Utah. Romney also scheduled campaign events in Minnesota, Illinois, Missouri, Tennessee, Georgia and West Virginia before arriving home Tuesday.
Colorado and Minnesota are caucuses states where a grass-roots effort could help secure a win, while West Virginia will award its delegates at a convention Romney plans to address before flying to Massachusetts to both vote and await the returns.
Romney has also deployed four of his five sons to Maine, Montana and Idaho, which hold caucuses on Saturday and Tuesday, and Alaska, which has a party convention on Tuesday.
If he fails to capture enough delegates to offset McCain's likely wins in other states and strong showing in California, where the Arizona senator has the backing of Gov. Arnold Schwarzenegger, Romney could end his campaign in Boston on Wednesday.
During a news conference Friday outside a Ford dealership here, he passed up three opportunities to declare he would carry on if he fails to surpass McCain in the Super Tuesday voting.
"I really thought it would all be over, you know, early in January, and now we're going to go into February, and I just can't predict what will happen in February," he said, "so we'll see what happens."
This week the multimillionaire former venture capitalist authorized only a modest $3 million advertising buy, after committing $35 million of his own money last year in an effort to lock up the nomination early with back-to-back wins in Iowa and New Hampshire.
While Romney won in Wyoming, Michigan and Nevada, McCain beat him in major head-to-head battles in New Hampshire, South Carolina and Florida. Huckabee prevailed in the leadoff Iowa caucuses. He has vowed to remain in the race, taking critical conservative support from Romney.
Currently, Romney trails McCain in delegates to the Republican National Convention, 83-59. A total of 1,191 are needed for the nomination.
Simple mathematics highlight the challenge confronting Romney.
California has 170 delegates at stake Tuesday, but it will award 159 of them - three at a time - to the winner in each of the state's 53 congressional districts.
If Romney and McCain were to split those delegates, the biggest bloc up for grabs Tuesday, they would each claim about 80 delegates.
Of the remaining states where Romney is personally campaigning, Colorado (43), Minnesota (38), Illinois (57), Tennessee (52) and Georgia (72) award their delegates in proportion to the vote percentage received by each candidate.
Only Utah (36), where Romney enjoys strong support from his fellow Mormons, Missouri (58), where he has the backing of Gov. Matt Blunt, and West Virginia (18), whose convention he will address, award all their delegates to the candidate winning the majority of votes on Tuesday.
McCain's home state of Arizona (53) and Delaware (18) are winner-take-all states, with North Dakota (23) being one as well if the winner gets two-thirds of the vote.
If Romney wins the winner-take-all states he visits and McCain won the others, the Arizona senator would outscore him on delegates, leaving Romney with the choice of either quitting or dumping more of his own money in a protracted battle for delegates. He has said that he and his wife have set a limit on their personal contribution to the race, although they have not divulged the figure.
Romney's only public appearance of the day was a rally in the jam-packed showroom of a Denver Ford dealer. He mentioned McCain only once as he sought to contrast his 25 years as a businessman with McCain's four terms in the Senate.
"At a time like this, in a country like this, I think it is important to have a president for whom the economy is his strong suit," Romney said to howls of support.
Earlier in the day, Romney conducted a series of satellite television interviews in Super Tuesday states, speaking to three markets in Illinois and one each in North Dakota, Missouri and West Virginia.
He also continued his outreach to bedrock conservatives he hopes are wary of McCain, conducting a conference call with conservative bloggers and sending out a series of e-mails highlighting or seeking additional conservative support.
Alaska Sen. Lisa Murkowski and former Sen. Rick Santorum of Pennsylvania also announced their endorsements of Romney, as did the Denver Post.
In addition, Sen. Jim DeMint of South Carolina sent an e-mail to conservatives, writing: "All of the major campaigns have had their moment in the sun, but now, with this race at a critical juncture, conservatives must no longer divide their votes. We must come together and rally behind the real consensus conservative in this race."
