WASHINGTON (AP) -- It's over, and Mitt Romney is going to be the GOP nominee for president.
That's the growing consensus among Republican National Committee members who will automatically attend the party's national convention this summer and can support any candidate they choose.
Even some RNC members who support other candidates begrudgingly say the math doesn't add up for anyone but the former Massachusetts governor.
"I would be surprised if Romney doesn't get the number he needs," said Jeff Johnson, an RNC member from Minnesota who supports former House Speaker Newt Gingrich.
Bob Bennett, an RNC member from Ohio, was more blunt.
"Look, Gov. Romney's going to be the nominee, and he's going to have enough votes," said Bennett, who is publicly neutral but said he supported Romney four years ago.
Romney's chief rival, former Pennsylvania Sen. Rick Santorum, is vowing to stay in the race, hoping a win in his home state's primary on April 24 will give new life to his campaign. But Santorum has fallen far behind Romney in the race for convention delegates, and RNC members are taking notice, even though most are publicly staying neutral, preferring to let primary voters decide the nominee.
The Associated Press has polled 114 of the 120 RNC superdelegates, party members who can support any candidate for president they choose at the national convention in August, regardless of what happens in primaries or caucuses.
Results from the latest survey conducted Tuesday to Friday: Romney has 35 endorsements, far more than anyone else but a modest figure for the apparent nominee. Gingrich has four endorsements, Santorum has two and Texas Rep. Ron Paul got one.
RNC members have been slowly embracing Romney -- he picked up 11 new endorsements since the last AP survey a month ago, after the Super Tuesday contests. Over the course of the campaign, however, Romney has methodically added endorsements from every region of the country. And in the U.S. territories, where voters help decide the nominee but can't vote in the general election, Romney has dominated.
Romney has endorsements from all three RNC members in Guam, American Samoa, the Virgin Islands and the Northern Mariana Islands. He was endorsed by two of the three RNC members in Puerto Rico.
Romney may be struggling among voters in the South, but he was endorsed by two of the three RNC members in Mississippi, Henry Barbour and Jeanne Luckey. Romney even has support from RNC member Robert Asher of Pennsylvania, the state Santorum represented in the Senate.
Santorum's only endorsements are from RNC members in Iowa and Alabama. In Pennsylvania, state GOP chairman Robert Gleason is publicly neutral.
"I talked to Rick the other day," Gleason said. "He didn't even ask me to support him."
Texas GOP chairman Steve Munisteri said he talked to Santorum for about 20 minutes on Tuesday, when Santorum was in Texas for a fundraising event.
Santorum told him "what I already believed, which is we're only a little over the halfway mark and that he thinks he'll do really well in the Southern states," said Munisteri, who has yet to endorse anyone.
"He should go into those states as the front-runner," Munisteri said of Santorum. "If he can win Pennsylvania, he'd then be able to put a streak of five or six wins together based on all the Southern states holding primaries."
Seventy-two RNC delegates said they were either undecided or not ready to make a public endorsement. Many said they are eager for the nomination fight to end so the party can focus on defeating President Barack Obama in November.
But most said they are reluctant to ask Santorum to quit.
"The decision to get in or get out of a race is an extremely personal decision," said John Ryder, an RNC member from Tennessee who is neutral. "He's got to decide when he thinks it is no longer politically valuable to continue."
"It is very hard to see any path for Sen. Santorum to the nomination. It is very hard to see any path for Speaker Gingrich to the nomination," Ryder said. "But they and their supporters have to make that final call."
In the overall race for delegates, Romney has 660 and Santorum has 281, according to the AP count. Gingrich is even farther behind, with 135, followed by Paul with 51.
Romney has won 58 percent of the caucus and primary delegates so far. At that pace, he would reach the number of delegates needed to clinch the nomination -- 1,144 -- on June 5, when voters got to the polls in five states, including delegate rich California and New Jersey.
Santorum met privately Thursday with conservative activists to work on plans to stop Romney's march to the nomination. The group decided to pressure Gingrich to leave the race, believing that would help unite conservatives behind Santorum.
Gingrich, however, has already scaled back his campaign to the point that he schedules few public events. In the three primaries last Tuesday, all won by Romney, Gingrich got 11 percent of the vote in both Maryland and the District of Columbia and 6 percent in Wisconsin.
Even if Santorum had picked up every vote for Gingrich, Romney still would have won all three primaries.
"It's over with," said Bennett, the RNC member from Ohio. "And if Romney carries Pennsylvania, that completes it. He'll be the presumptive nominee before the end of the month."
Associated Press writers Brian Bakst in St. Paul, Minn.; Kantele Franko in Columbus, Ohio; Peter Jackson in Harrisburg, Pa.; and Will Weissert in Austin, Texas, contributed to this report.