Voters in Taiwan face a critical decision on Saturday: whether to throw out 24 opposition lawmakers they elected just last year, in an extraordinary recall campaign that could put more power in the president’s hands but add to tensions with Beijing.

The vote threatens to flip the legislative balance in favor of President Lai Ching-te, who wants Taiwan to forge a future separate from China, against an opposition that favors closer ties with Beijing.

China, which claims the island as its territory and has been wary of Mr. Lai, could step up pressure on Taiwan if voters oust a large number of the lawmakers and give Mr. Lai more room to pursue his agenda. Here is what is at stake and how the recall will work:

A Triumph or a Travesty of Democracy?

No national-level legislatures worldwide have faced a recall effort as extensive as Taiwan’s, said Yanina Welp, a research fellow at the Graduate Institute in Geneva who studies recall initiatives.

Taiwan is one of the few democracies that allows voters to throw out elected representatives through such petitions, but previous campaigns were smaller and rarely successful.

This weekend, two dozen Nationalist Party lawmakers face recall votes; an additional seven will next month.

To supporters, the “great recall” campaign reflects the vigor of Taiwan’s democracy, which emerged in the 1980s after decades of authoritarian rule under the Nationalist Party. Although a successful campaign would help Mr. Lai, many activists promoting the recalls say they are acting independently.