Republican presidential hopefuls eager to demonstrate their foreign policy credentials on the campaign trail have homed in on China, a topic that allows them to assail President Biden while focusing less on global issues more divisive with primary voters.

While the candidates are in near-unanimous agreement that Beijing is the United States’ foremost foreign adversary, their remarks and policy prescriptions reveal significant divides within their party on how to approach it.

Former Vice President Mike Pence used a China-focused speech on Monday at the Hudson Institute in Washington to criticize Donald J. Trump, his former running mate and the race’s front-runner, and other competitors as being isolationist. Nikki Haley, who was one of Mr. Trump’s ambassadors to the United Nations, has suggested he was not aggressive enough on China.

Vivek Ramaswamy, in a policy speech on Thursday at a packaging plant in New Albany, Ohio, attacked the protectionist trade policies that have been promoted by some in the party, including Mr. Trump.

Still, to a large extent, the Republican contenders have all raced to see who can be the most hawkish toward Beijing, following a path set by Mr. Trump in 2016 when he made attacking China a central policy plank and then sharply hardened America’s trade policy toward the country. By focusing on China, the candidates can make detailed policy pronouncements and play up their credentials, yet avoid discussion of Russia or Ukraine, an increasingly divisive topic among Republicans.

All of the candidates have blasted President Biden’s attitude toward China. Mr. Biden has sought to stabilize relations after escalating espionage accusations inflamed tensions. But he has also tried to counter Beijing’s growing global influence with a multilateral approach, aiming to shore up economic and diplomatic ties with regional allies.

One of the Biden administration’s focal points has been targeting China’s semiconductor industry. The administration has enacted export controls and helped push the CHIPS and Science Act, a bipartisan law that provided billions of dollars toward fostering a homegrown semiconductor industry that could make America less dependent on foreign suppliers.

But even that bipartisan effort has come in for criticism. On Thursday, as Mr. Ramaswamy stood miles away from the site of a new Intel chip manufacturing complex that will be assisted by the CHIPS Act, he attacked the law for including provisions related to addressing climate change.

“I am opposed to the CHIPS Act,” he said, “because it is really the Green New Deal masquerading in CHIPS masquerade clothing.”

He also claimed without evidence that China had propagated the “climate change agenda” in order to hamper American industry.

Mr. Ramaswamy also said he would focus on job training programs to develop a stronger work force for a robust chip industry. Doing so, he added, would make the United States less reliant on Taiwan, the world’s biggest chip producer, and reduce the threat that a Chinese attack on Taiwan might pose on American interests.

Mr. Ramaswamy has previously suggested he would be less committed to defending Taiwan if the United States were less reliant on its semiconductors. That view, and his suggestion that Ukraine concede territory to Russia, have drawn fire from Mr. Pence and Ms. Haley.

In his speech on Monday, Mr. Pence, who emphasized his role in crafting the Trump administration’s China policy, did not single out Mr. Ramaswamy. But he used the threat of Beijing as a lens through which he could posit his larger view of foreign policy: that America could not retrench from decades of global leadership.

He accused some candidates of “abandoning the traditional conservative position of American leadership on the world stage, and embracing a new and dangerous form of isolationism.”

Mr. Pence also criticized President Biden over the U.S. military’s chaotic withdrawal from Afghanistan, suggesting it had shown weakness on the world stage to China. (The Biden administration has said it was constrained in its options for ending the nation’s longest war by decisions made during the Trump-Pence administration.)

During his term, Mr. Trump imposed tariffs on more than $360 billion worth of Chinese goods, initiating a protracted trade war that eased somewhat when the United States and China signed a trade deal in early 2020. Seeking the nomination, his talk on economic issues has been combative even as he has praised China’s president, Xi Jinping, for his “iron fist” leadership.

He has vowed to “completely eliminate U.S. dependence on China,” in part by reducing imports, restricting American companies’ ability to invest there and revoking the “most favored nation” trade status.

Ms. Haley said earlier this year that she believed Mr. Trump had been so focused on trade that he ignored other Chinese threats.

At town halls in New Hampshire on Thursday, she warned that China was outpacing the United States in shipbuilding and developing “neuro-strike weapons” that she said could be engineered to change brain activity and be used to target military commanders and segments of the population.

China was more than just an economic rival, she suggested.

“They don’t see us as a competitor,” Ms. Haley said. “They see us as an enemy.”

Jazmine Ulloa contributed reporting from Bedford, N.H.