Supreme Court nominee Brett Kavanaugh's views on gun rights may push the court to expand Second Amendment protections, say senators and activists on both sides of the debate.

A 2011 Kavanaugh opinion, arguing for striking down the District of Columbia's assault-weapons ban, suggests that he would be a stronger gun-rights advocate than the justice President Donald Trump has chosen him to replace, Anthony Kennedy.

"Judge Kavanaugh is the worst nightmare for any advocate of common-sense gun violence prevention," Sen. Richard Blumenthal, D-Conn., said. "Any measure preventing gun violence is at risk if it's Justice Kavanaugh."

Where Democrats are fearful, pro-gun conservatives are optimistic that a Supreme Court with Kavanaugh in place of Kennedy would expand gun rights. The court hasn't taken up a gun-rights case since 2010, and it has bypassed numerous chances to do so despite calls from some conservative justices.

"If some state has banned semi-automatic weapons, they could rule that the Second Amendment trumps that state law," Sen. Lindsey Graham, R-S.C. "Once the case gets there, I hope he'll listen to both sides of the story. Is he more conservative than Justice Kennedy on some issues? I think so."

"This was all part of an election. President Trump said he would put constitutional conservative judges who would protect the Second Amendment. That's what he's doing," Graham said.

The National Rifle Association's top lobbyist Chris Cox praised Kavanaugh as an "outstanding choice" with "an impressive record that demonstrates his strong support for the Second Amendment." The NRA has argued that bans on semi-automatic rifles, along with minimum age requirements and waiting periods for firearm sales, are unconstitutional.

At the center of the conversation is Kavanaugh's 2011 dissenting opinion that said he would strike down the District of Columbia ban on some assault weapons and a requirement that all firearms be registered. A 2-1 majority upheld the assault-rifle ban and some of the registration rules.

Kavanaugh said he sympathized with the intent of the measures, but said that "the Supreme Court has long made clear that the Constitution disables the government from employing certain means to prevent, deter or detect violent crime."

"A ban on a class of arms is not an 'incidental' regulation. It is equivalent to a ban on a category of speech," Kavanaugh wrote. "As I read the relevant Supreme Court precedents, the D.C. ban on semi-automatic rifles and the D.C. gun registration requirement are unconstitutional and may not be enforced."

His opinion raised alarms among gun-control advocates including former Rep. Gabrielle Giffords, a Democrat who in 2011 was shot in the head at point-blank range during a constituent meeting in her hometown of Tucson, Arizona. She warned that Kavanaugh has "expressed a dangerous hostility toward reasonable gun regulations."

Sen. Dianne Feinstein of California, the top Democrat on the Judiciary Committee, labeled Kavanaugh's views on gun rights "extreme," and said Wednesday she intends to question the nominee about them when he appears before the Senate.

The two Republican-appointed judges in the majority of the 2011 appellate panel said the D.C. laws were consistent with the Supreme Court's 2008 decision in District of Columbia v. Heller. That 5-4 ruling, written by then-Justice Antonin Scalia and joined by Kennedy, established an individual right to possess a gun in the home for lawful purposes such as self-defense.

The decision said that Second Amendment rights are "not unlimited" and that certain restrictions are permissible, including bans on "dangerous and unusual weapons."

As an appellate judge, Kavanaugh is bound by Supreme Court precedent. As a justice, he would be be freer to vote to alter it based on his interpretation of the Second Amendment.

The issue looms large before the Nov. 6 congressional elections, when control of the Senate is up for grabs - and with it, the authority to confirm or reject future nominees to the Supreme Court.

The Supreme Court last heard arguments and ruled in a Second Amendment case in 2010, when it extended Heller's gun protections to state and local governments in ruling that Chicago couldn't ban possession of a handgun in the home. Since then, the justices have turned away at least 15 constitutional gun-rights cases, including several appeals that sought the right to carry a weapon in public and challenged bans on semi-automatic assault rifles.

Kavanaugh could tip the balance, potentially giving the court the necessary fourth vote to take up a case as well as a fifth vote to overturn restrictions and extend the constitutional protections.

"A Justice Kavanaugh will likely shift the court to the right on gun issues. Kavanaugh has a very aggressive view of gun rights, one that's very hostile to gun control," said Adam Winkler, a professor at the UCLA School of Law and author of the 2011 book "Gunfight: The Battle over the Right to Bear Arms in America."

Trump's first Supreme Court appointee, Justice Neil Gorsuch, indicated last year he would bolster the Second Amendment. He joined Justice Clarence Thomas in saying the court should have scrutinized a San Diego County policy that required people to show a that it was necessary to carry a concealed handgun outside the home.

"For those of us who work in marbled halls, guarded constantly by a vigilant and dedicated police force, the guarantees of the Second Amendment might seem antiquated and superfluous," Thomas wrote for himself and Gorsuch. "But the framers made a clear choice: They reserved the right to bear arms for self-defense."

Two other members of the court, Chief Justice John Roberts and Justice Samuel Alito, were in the five-justice majority when the court ruled in 2008 that the Second Amendment protects individual gun rights.

Winkler said Kavanaugh could provide the fourth vote necessary to take up a case.

"It seems pretty clear that Justice Kennedy was not a vote for cert," Winkler said, using a term for granting review. "It seems pretty clear that Judge Kavanaugh would be a vote for cert."

About eight states, including California and New York, bar most people from carrying weapons in public. Those two are also among the seven states that bar semi-automatic assault rifles.

Some prominent conservatives believe it's only a matter of time before the Supreme Court reviews a challenge seeking to invalidate those types of gun control laws.

"It'll be an issue that will be back before the Supreme Court," said Sen. John Kennedy, R-La.