WASHINGTON (CNN) -- Sen. John McCain moved to shore up his support among conservatives by pledging Tuesday to nominate strict constructionist, conservative judges to the federal bench.

"It will fall to the next president to nominate hundreds of qualified men and women to the federal courts, and the choices we make will reach far into the future," the presumptive Republican presidential nominee said during a speech at Wake Forest University in North Carolina.

"My two prospective opponents and I have very different ideas about the nature and proper exercise of judicial power," he said, referring to Sens. Hillary Clinton and Barack Obama.

"We would nominate judges of a different kind, a different caliber, a different understanding of judicial authority and its limits." Watch more of McCain's comments »

Many conservative members are suspicious of McCain on the issue of judges because of his involvement in 2006 in the Senate "gang of 14."

That bipartisan group of senators sought to reach a consensus on President Bush's judicial appointees, blocking some of the president's most conservative nominations while promising to confirm others.

The group formed after the then-Senate Majority Leader Bill Frist threatened to remove the ability to filibuster judicial nominations after Democratic senators blocked a number of Bush nominees.

But many conservatives responded positively to McCain's speech.

"[It was a] strong speech ... Very encouraging. McCain has drawn a clear line between his support for judicial restraint and Obama's promise to appoint liberal judicial activists," said Ed Whelan, president of the Ethics and Public Policy Center and a former law clerk for Justice Scalia.

"McCain has promised that his Supreme Court nominees will have 'a proven record of excellence in the law, and a proven commitment to judicial restraint ...

"McCain has embraced both John Roberts and Samuel Alito as model nominees. McCain clearly recognizes that liberal judicial activism deprives Americans of their basic powers as citizens to establish policies through their legislators."

McCain also criticized Obama for not voting to confirm Supreme Court Justice Samuel Alito, saying the Illinois senator's justification of that decision sounded like it was written by an "activist judge."

"Apparently, nobody quite fits the bill except for an elite group of activist judges, lawyers and law professors who think they know wisdom when they see it -- and they see it only in each other," McCain said of Obama.

Responding Tuesday to McCain's claims, Obama campaign spokesman Tommy Vietor said, "The Straight Talk Express took another sharp right turn today as John McCain promised his conservative base four more years of out-of-touch judges that would threaten a woman's right to choose, gut the campaign finance reform that bears his own name, and trample the rights and interests of the American people.

"Barack Obama has always believed that our courts should stand up for social and economic justice, and what's truly elitist is to appoint judges who will protect the powerful and leave ordinary Americans to fend for themselves."

Meanwhile, Clinton campaign Policy Director Neera Tanden responded by saying, "We won't take lectures on the right way to approach the Constitution from Sen. McCain, who voted for extreme conservative judges like Justice [Clarence] Thomas.

"In an effort to pander to conservative voters, Sen. McCain has signaled his intention to appoint right-wing judges who are committed to rolling back women's rights and civil rights, elevating the interests of big business over the rights of workers and consumers, affirming executive branch power grabs, and undermining our common core freedoms."

Democratic National Committee Chairman Howard Dean said McCain has a "radical, right-wing judicial philosophy."

"It's clear he's the wrong choice to safeguard that future," Dean said.

"No matter how far they have gone to restrict our fundamental rights or their clear records of gutting the reforms John McCain claims to care about, he has put loyalty to his party and a radical agenda ahead of the American people."

CNN Political Producer Peter Hamby contributed to this report.

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