WASHINGTON – The second Republican senator to meet with Supreme Court nominee Merrick Garland exited her sit-down with the appeals court judge Tuesday declaring that she was “more convinced than ever that the process should proceed.”

“The next step, in my view, should be public hearings before the Judiciary Committee so that the issues that we explored in my office can be publicly aired,” Sen. Susan Collins, R-Maine, told reporters who staked out the hour-long morning meeting on Capitol Hill.

Those words were music to the ears of Senate Democrats and White House officials who are hammering away at the blockade established by top Republican leaders. But there is a big catch: Collins supported hearings even before the meeting, and 14 other Republicans who have agreed to meet with Garland say they will tell him they are opposed to election-year action on his nomination.

Garland’s meeting with Collins kicked off a whirlwind round of Tuesday sit-downs, part of the charm offensive that White House officials hope will force Republicans to take up his confirmation.

Later in the day, Garland met with two Democrats — Jeanne Shaheen of New Hampshire and Joe Manchin of West Virginia — as well as another Republican, John Boozman of Arkansas.

Boozman, a more conservative senator than Collins representing a more conservative state, was expected to be a much tougher nut for Democrats to crack, and he handled his meeting with Garland much differently from Collins or Mark Kirk, R-Illinois, who invited reporters and photographers into their offices to document the visits.

Boozman did not emerge to greet Garland in front of cameras, and the meeting — which did not last much longer than 10 minutes — was considerably shorter than Garland’s other recent Senate meetings.

He issued a brief statement afterward, explaining that he “conveyed to Judge Garland my position, which is that the next president should fill the vacancy.”

“My position is firm,” he said. “That means I will not advocate for hearings or a vote, nor will I support filling the vacancy with President Obama’s pick after the election.”

Collins said Tuesday that it was “premature” to say whether she would support Garland in a floor vote but said she “found the judge to be extremely straightforward” during a lengthy conversation that touched on the Second Amendment, the limits of executive power and the role of the court in American life.

“He gave very thorough, impressive responses to all of my questions,” she said.

Asked about the blockade favored by Grassley and Senate Majority Leader Mitch McConnell, R-Kentucky, Collins said the Senate is “best served by following the regular order” but added that she was “not optimistic that I will be changing minds on this issue.”

She added, “It would be ironic if the next president happens to be a Democrat and chooses someone who is far to Judge Garland’s left.”

Other key meetings between Garland and Republicans are coming together in the weeks ahead: Sens. Kelly Ayotte (New Hampshire) and Rob Portman (Ohio), who are up for re-election in November and have been subjected to special pressure, will meet with Garland separately on April 14. And in a Monday phone call, Senate Judiciary Committee Chairman Charles E. Grassley invited Garland to have breakfast at a time and place to be announced.

Carrie Severino, chief counsel for the Judicial Crisis Network, which has organized conservative opposition to Garland’s confirmation, said those senators will act more like Boozman than Collins.

“These meetings are non-events, no matter how badly the White House wishes the opposite were true,” she said in a statement. “The only reason we hear anything about these courtesy meetings is that the White House is desperate to spin every act of political theater into a sign of life for the nomination.”

Meanwhile, Democrats kept up the pressure in other ways Tuesday. A liberal activist group, Center for American Progress Action, organized a group of more than 30 advocates from key states represented by Republicans who are opposed to Garland’s confirmation. The advocates, who include former judges, current and former elected officials, and military veterans, met with their home-state senators throughout the day.

Also Tuesday, Senate Minority Leader Harry M. Reid, D-Nevada, used his daily floor remarks to renew his attacks on Republicans. He took special aim at Jerry Moran of Kansas, who told a home-state crowd that he favored hearings on Garland last month before reversing himself Friday after fierce attacks from conservative activists.

Reid, citing a Kansas newspaper report, accused Moran of succumbing to influential conservative donors, including the Koch brothers. One brother, Charles Koch, lives in Wichita and is a major political force in the state.

“He dared to do his job,” Reid said of Moran. “Regrettably, Senator Moran is just the latest Republican senator to allow himself to be pushed around, to be intimidated by money. Instead of caving to the Republican lender, the Koch Brothers, it is time for the Republican members to take a stand.”

While no new GOP senators have joined Collins and Kirk in calling for hearings, Reid said at an afternoon news conference that he was confident the Republican siege would ultimately crumble. He did not rule out using procedural maneuvers to force a vote on Garland’s confirmation.

“Certainly, we’ve got that arrow in the quiver to do that and other things if we choose,” he said. “But right now, I think we’re in a good place.”