The day after Tuesday's election, Clark County officials were still processing more than 66,000 ballots that will help determine the outcome of a tight U.S. Senate race

Incumbent Sen. Jacky Rosen (D-Nev.) and Republican Sam Brown will go head to head Tuesday in the Nevada Senate race. Rosen, a first-term senator, has held a steady lead throughout the cycle, buoyed by a fundraising and spending advantage that has helped keep Brown at arm’s length ever since his primary victory in June.

Democratic Sen. Jacky Rosen trailed Republican Sam Brown by less than 1,000 votes as Nevada counties stopped reporting results early Wednesday morning. As of Wednesday at 3 a.m., Brown led Rosen by 870 votes — or 0.

Nevada Democrat Jacky Rosen is in a neck-and-neck battle in her bid to return to the U.S. Senate for a second term, while her party lost its slim voting majority in the upper chamber of Congress.

Nevada, a critical swing state, remains a key focus in the 2024 presidential race between Kamala Harris and Donald Trump. Although Nevada has leaned Democratic in recent elections, the state’s significant Latino population,

Sam Brown, a Republican newcomer, is a West Point graduate who was nearly killed by a roadside bomb in Afghanistan. His thin political résumé could help him. Senator Jacky Rosen, a Democrat, isn’t flashy, but the power of incumbency matters.

Results for the 2024 Nevada U.S. Senate Class I general election. Find Nevada and national elections results at BostonGlobe.com.