"I have a pretty long list of concerns, but Republicans tend to be loyalists," said Michael D. Zimmer, a Carroll County commissioner who originally backed Rep. Tom Tancredo of Colorado. "I don't think there will be quite the same level of intensity at the grass roots for McCain as for, say, a Mitt Romney."
In the span of eight weeks, the Arizona senator rebounded from a third-place Iowa finish to win in New Hampshire and dominate on Super Tuesday. He vanquished younger and better-financed opponents who said he was too moderate, too old or too hawkish to lead his party.
McCain's quick comeback has given supporters of former Tennessee Sen. Fred Thompson, former New York Mayor Rudolph W. Giuliani and others little time to embrace a candidate they once saw as not worthy of support.
Among the troubles for Zimmer and other right-of-center Maryland Republicans: McCain views that include his initial opposition to President Bush's tax cuts and an unwillingness to fight for the administration's judicial nominees, as well as his push for campaign finance reform and immigration proposals.
Some Republicans say questions about McCain have abated in the weeks since his nomination became a foregone conclusion.
"I've been very surprised at how the bulk of the party regulars have come together so quickly," said Chris Cavey, chairman of the Baltimore County Republican Party and initially a Thompson backer. "Sure, there are some who are zealous and very committed to their cause - and there are some who will make a point by staying home - but I think it will be a tiny number."
Still, enthusiasm for McCain has plenty of room to grow among rank-and-file Republicans, said state Sen. Alex X. Mooney of Frederick County, where former Arkansas Gov. Mike Huckabee came within about 3,500 votes of beating McCain when Maryland voted Feb. 12.
"Is it there right now? Not so much that I see," said Mooney, who was a vice chairman of Romney's Maryland steering committee. "But can he and will he generate it? He probably will."
Mooney and other Republicans see two significant decisions ahead that will assist McCain's candidacy.
The first: a running mate selection. If McCain chooses a vice presidential nominee with strong conservative views, many party leaders will applaud, they say.
The second will come when the Democrats pick their candidate. Many Republicans relish the prospect of a campaign against either Sen. Barack Obama, whom they view as disturbingly liberal, or Sen. Hillary Clinton, who is considered to be polarizing.
"He will have an opponent who is going to be far left," Mooney said.
Del. Christopher B. Shank, the state House Republican whip from Western Maryland, said that suggestions from some that Republicans reject McCain or vote for Clinton were "absolute lunacy."
"A lot of this talk about not supporting John McCain is coming from the talking heads who are not as connected to the grass roots as they think they are," said Shank, a Huckabee backer who saw his favored candidate nearly win in Washington County last month.
After delegates from Texas mathematically assured his nomination, McCain took major steps yesterday toward bringing various elements of the Republican Party under his control.
At the White House, Bush praised McCain's "courage and strength of character and perseverance" and pledged to support him in any way the senator wants.
"I'm going to find ample time to help," Bush said. "And I could help raising money. And if he wants my pretty face standing by his side at one of these rallies, I'll be glad to show up."
McCain brushed aside concerns that an association with Bush - whose approval rating remains in the low 30s - could do more harm than good.
"I hope that he'll campaign for me as much as is in keeping with his busy schedule," McCain said.
Later, at Republican National Committee headquarters, Chairman Mike Duncan said the party had $25 million in available cash to promote McCain's candidacy, as well as research and other resources.
Overall, Maryland Republicans backed McCain over Huckabee 55 percent to 29 percent in last month's primary. The outcome fit the state's long pattern of supporting moderate or pragmatic Republicans, including former Sen. Charles McC. Mathias Jr. and Governors Theodore R. McKeldin, Spiro T. Agnew and Robert L. Ehrlich Jr.
But McCain's support from Maryland Republican leaders has been weak. His backers note with wistfulness that many of the 20 at-large McCain delegates and alternates that Maryland will send to the national convention in Minneapolis-St. Paul this summer will have switched allegiances from other candidates. In short, there aren't enough prominent McCain allies to fill the spots.
McCain's Maryland victory also belies a relatively flimsy party structure that is available to assist the former Naval Academy graduate in the months ahead.
Since Ehrlich's 2006 re-election defeat, "it's no secret that the state GOP is struggling," Mooney said. "They are just trying to keep themselves afloat."
Maryland, expected to stay in the Democratic column in the general election, will likely reprise its role as a donor state - a place where the nominee can come to raise money more effectively used elsewhere.
"It is a nice quick trip from his headquarters, and I'm sure he wants to tap into Maryland's monetary resources and the Baltimore-Washington media market," Cavey said.
Richard E. Hug, a businessman and major fundraiser for Ehrlich and Bush who backed Giuliani this year, said he is remaining on the sidelines "for the time being."
Before helping McCain, "I'd have to be absolutely convinced that what he's saying now is what he believes," said Hug, noting the senator's votes against Bush tax cuts but more recent support of them. "So we'll see."